Compare commits

..
Author SHA1 Message Date
Niels Lohmann 2fb2be036c Check the CSV file and the round count in the json_view benchmarks
fopen() of the CSV output was not checked, so an unwritable directory made
fprintf() write to a null FILE*; the round count is parsed with strtol and
clamped instead of atoi.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:56 +02:00
Niels Lohmann 91125c26a3 Add a timeout and a concurrency group to the json_view benchmarks
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:55 +02:00
Niels Lohmann ffedc9dcb6 Make the downloads of json_view's compare.py robust
Hash the archives in chunks instead of reading them into memory, download
with a timeout, extract into a temporary directory that is renamed into
place only after success (a half-extracted directory was trusted forever),
and split CXX and CC into arguments so that values like 'ccache g++' work.
Note at the pins that a SHA-256 mismatch of a GitHub tag archive means
that GitHub regenerated it.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:54 +02:00
Niels Lohmann 2188623289 Compare json_view with yyjson, simdjson, and Boost.JSON
tests/benchmarks/json_view/ holds a comparison with other
libraries, answering the question users ask when they pick one.
It is not built by CMake and not run by CI.

- bench_view.cpp: parse, traverse, select and dump of twitter,
  citm_catalog, canada, jeopardy, a tweet and an RPC request,
  against json_view, yyjson, simdjson, Boost.JSON and json::parse,
  all agreeing and run interleaved.
- bench_corpus.cpp: parse, traverse and dump of any file list.
- bench_edit.cpp: parses, edits through each library's own API,
  and serializes; all outputs must describe the same value.
- compare.py: builds both programs with system or pinned,
  SHA-256-checked downloads, and writes results with the commit,
  CPU, OS, compiler and library versions.
- README.md and a workflow that runs on demand or via a PR label.

Fairness fixes folded in: each engine runs once untimed before
each timed round, so the next one no longer pays for the
previous one's cleanup; dump is also compared with source numbers
against yyjson's raw-number mode; a "simdjson DOM (fresh)" column
and a reused-document column for json_view were added;
compare.py's paths are absolute; downloads use a .part file and a
failed checksum removes the archive.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:53 +02:00
Niels Lohmann 765b9dd790 Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:51 +02:00
Niels Lohmann 7985a0b466 Move the dump tests of this branch to unit-json_view_dump.cpp
The dump and comparison tests moved to their own file in the dump pull
request; the tests of the fast dump() join them there.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:50 +02:00
Niels Lohmann 4981016097 Split the value and pointer edit tests off unit-json_view_edit.cpp
The MinGW linker of the Windows clang jobs cannot link object files with more
than 32767 sections ("relocation truncated to fit: IMAGE_REL_AMD64_REL32
against `.rdata'"). unit-json_view_edit.cpp has 35409 sections since the fast
dump instantiates more code for editable documents, so its test cases "views
and values", "deeply nested values", "pointers below a null value", and
"strings of other documents are checked" move into
unit-json_view_edit_values.cpp. The helper exception_of_call() that both
files use moves into json_view_test_helpers.hpp.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:49 +02:00
Niels Lohmann 720874a550 Write doubles from their bits only where double is IEEE 754 binary64
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:49 +02:00
Niels Lohmann cf22dc3e7c Fix clang-tidy 22 findings in unit-to_chars.cpp
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:48 +02:00
Niels Lohmann 76bb7407f9 Test write_short_decimal and powers_of_ten_16 against to_chars
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:47 +02:00
Niels Lohmann 68e9b48a7c Use a named document in the dump test: root() of a temporary does not compile
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:46 +02:00
Niels Lohmann 6d8e3dbf08 Tidy the view serializer: doxygen block placement, enabled() for a constant
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:45 +02:00
Niels Lohmann 15a865daf2 Fix out-of-bounds read when dumping a float token of an unchecked image
A float node of an image loaded with image_check::bounds can hold a
token whose bytes are not digits, so its value need not have the digit
count recorded in the node. write_double_at() passed that count to
write_short_decimal(), which indexes its table of powers of ten by it:
an assertion failure in debug builds, an out-of-bounds read in release
builds. Use the counted overload only if the value has exactly that many
digits, otherwise count them.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:44 +02:00
Niels Lohmann c53842f7ae Fix MSVC C4127 and Infer finding in the view serializer
Test the template options through enabled() so that conditions combined
with them are not constant, and mark the nav::value() null dereference
as a false positive like materialize.hpp does.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:43 +02:00
Niels Lohmann 860a214322 Write json_view's dump() without a call or conversion per token
The default dump() (no indentation, no ensure_ascii) gets its own
writer that makes the same walk and produces the same output:

- the write position stays in a local variable instead of a
  member, so the compiler keeps it in a register across stores
  through aliasing char pointers;
- strings and number tokens are copied with fixed-size 32-byte
  moves wherever enough source bytes remain, instead of one
  memcpy call per token;
- the innermost open container lives in local variables; a stack
  that starts as a local array of 32 entries holds the rest;
- unedited documents are walked through the node array in order,
  and integer tokens are read from the source directly.

On top of that, float tokens of at most 15 significant digits are
written straight from their digits via zmij::to_shortest() and
write_shortest(), without converting to a double and back: such
decimals are farther apart than a double's rounding interval, so
the token's digits are the double's shortest digits. Tokens of
16+ digits, or edited values, still go through decimal_to_float().
The view's own NEON write_decimal() is removed in favor of the
shared writer, and the dump output now grows in 64 KiB steps
instead of being resized to its estimate at once.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:42 +02:00
Niels Lohmann 1a4e4d806c Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:40 +02:00
Niels Lohmann 4c78fbb85f Build the image link test without exceptions
load_result() exists only with exceptions; with JSON_NOEXCEPTION the test
loads the image with the check directly (a failed check aborts).

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:39 +02:00
Niels Lohmann d8a11a131d Silence a clang-tidy C++17 finding in the image test
bugprone-suspicious-stringview-data-usage flags data() of the source view
under C++17, although the length is passed and checked by the REQUIRE
before it.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:38 +02:00
Niels Lohmann 767a55bad2 Make json_view.hpp pass include-what-you-use
ci_single_binaries runs IWYU with --error on every header. For json_view.hpp
it suggested adding <array> (std::array is used), the headers that json.hpp
already provides (abi_config, abi_macros, input_adapters, json_pointer,
cpp_future, string_concat, value_t, json_fwd), and <version> for
std::nullptr_t, and removing <cstddef>.

- include <array>
- keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>)
- tell IWYU not to suggest the headers that json.hpp provides: the amalgamated
  json_view.hpp only includes json.hpp, so including them here would duplicate
  their definitions
- drop edit_storage.hpp, which edit.hpp includes

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:38 +02:00
Niels Lohmann 1c87e8283b Fix the indentation of a loop in the image test
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:37 +02:00
Niels Lohmann 5690d776d5 Fix MSVC C4244 and C2017 in the image test
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:36 +02:00
Niels Lohmann 01be361251 Fix clang-tidy 22 findings in unit-json_view_image.cpp and image.hpp
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:35 +02:00
Niels Lohmann 27d3897e0e Avoid useless casts of header fields in the image tests
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:34 +02:00
Niels Lohmann 66f880d22a Expect first-wins lookups in the image tests
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:33 +02:00
Niels Lohmann f58ce0bf6d Document that editable documents refuse invalid UTF-8 copied from a loaded image
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:32 +02:00
Niels Lohmann a1de9a56f6 Test that invalid UTF-8 of a loaded image is not copied into an editable document
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:31 +02:00
Niels Lohmann 2d6ead2eff Release the list of large objects once load() has built the indexes
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:31 +02:00
Niels Lohmann 70136a68ec Test lookups in loaded images with duplicate and colliding keys
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:30 +02:00
Niels Lohmann 43a53a8abf Test that the targets of links never reach an image
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:29 +02:00
Niels Lohmann e4869ae29d Adapt the image tests to named documents and last-wins lookups
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:28 +02:00
Niels Lohmann 84e36d5f6f Check each distinct string and float range once in the full image check
The full check scanned the contents of every string node and every float token over its own range, so many nodes pointing to one large range made load() quadratic. The structural walk now only collects the ranges; after it, each kind is sorted and checked once per distinct range. Ranges of one kind that overlap without being identical are rejected, as save() never writes them (nodes that share a value share the whole range). The cost is linear in the size of the image plus sorting the ranges.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:27 +02:00
Niels Lohmann 4430b636d5 Fix MSVC errors in image test and add image_check doc anchor
Move the raw string literal out of the CHECK macro (MSVC preprocessor),
cast 64-bit header fields to std::size_t (C4244 on 32-bit), and give the
image_check section in load.md a real anchor for the mkdocs strict build.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:26 +02:00
Niels Lohmann 176eeedd07 Add images of json_documents: save() and load()
An image is a document stored so that loading it needs no
parsing: save() writes the node index, the text and the decoded
strings; the static load() reads an image written by save().

load() takes a pointer and size, a borrowed vector, or an owned
rvalue vector; the nodes are copied so they are aligned and can
be edited, while the text and decoded strings stay in the image.

image_check controls how much load() trusts the input: full
checks structure, bounds, strings and numbers, the parser's own
guarantees; bounds checks structure and bounds only; none skips
all checks, for images from a trusted source.

Layout is little-endian only ("NJVI" header, nodes, text, decoded
strings), following the idea of zero-copy formats such as
FlatBuffers and YaFF; the check follows FlatBuffers' Verifier.

New errors: parse_error.116 for a malformed image or a failed
check, type_error.320 for a discarded document or a big-endian
target.

A dedicated fuzzer and 6,000 seeded corruptions, checked under
ASan/UBSan, found and fixed two gaps: unchecked reserved header
fields, and unbounded null/boolean offsets that could make
dump() throw std::length_error.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:25 +02:00
Niels Lohmann ce31f2aecf Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:23 +02:00
Niels Lohmann e642e5507d Keep the view's edit headers clean for clang-tidy in C++17 mode
clang-tidy 22 checks the headers with -std=gnu++17 as well, where it asks
for a transparent comparator and std::make_unique. The regions map uses its
default comparator, and the allocation of the edit state keeps new (the
library is C++11) with a NOLINT.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:22 +02:00
Niels Lohmann befbafca02 Make json_view.hpp pass include-what-you-use
ci_single_binaries runs IWYU with --error on every header. For json_view.hpp
it suggested adding <array> (std::array is used), and the headers that json.hpp
already provides (abi_config, abi_macros, input_adapters, json_pointer,
cpp_future, string_concat, value_t, json_fwd), plus <version> for
std::nullptr_t, and removing <cstddef> and edit_storage.hpp.

- include <array>
- keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>)
- tell IWYU not to suggest the headers that json.hpp provides: the amalgamated
  json_view.hpp only includes json.hpp, so including them here would duplicate
  their definitions
- drop edit_storage.hpp, which edit.hpp includes

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:21 +02:00
Niels Lohmann 279009e7c3 Keep a raw string with a backslash out of a CHECK (MSVC C2017)
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:20 +02:00
Niels Lohmann e4c23e568e Fix clang-tidy 22 findings in unit-json_view_edit.cpp and edit.hpp
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:20 +02:00
Niels Lohmann 070396235f Fix clang-tidy 22 findings in the json_view headers
Silence bugprone-casting-through-void for the SSE loads (a reinterpret_cast
would trip -Wcast-align=strict), use auto for a cast initialiser, add
parentheses to a mixed expression, and name bugprone-std-namespace-modification
in the NOLINTs of the tuple_size/tuple_element specialisations.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
(cherry picked from commit 0effbaa7a2)
2026-10-11 12:45:19 +02:00
Niels Lohmann 17c0db7b07 Fix MSVC C4127 in the lookups of editable json documents
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:18 +02:00
Niels Lohmann 347de0a8d0 Assign the first member when set() meets duplicate keys again
Lookups find the first member of a repeated key again, so set(object, key,
value) assigns that member (keeping the key where it is) and drops the
others, as documented before, and a view taken from object[key] shows the
new value. This undoes the code and documentation changes of 5cbb8e6d6.
Lookups in edited objects (navigation of editable documents) stop at the
first match, like those of parsed objects.

The tests that commit added expect the first member from lookups now. In the
seeded differential test, the documents with repeated keys repeat them after
the real members; the reference holds the first members, which the edits
address and the lookups are compared with, while materialize() is compared
with what parse() makes of the document's dump.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:17 +02:00
Niels Lohmann e2c2fe9364 Assign the member that lookups find when set() meets duplicate keys
An editable document reads the last member of a repeated key (as the
read-only document does), but set(object, key, value) assigned the first
one: a view taken from object[key] before the call did not show the new
value. It now assigns the last member's value, keeps the key at the
position of its first occurrence (where materialize() puts it), and drops
the other members.

The seeded differential test now also edits documents whose objects
repeat keys and compares every lookup (operator[], at, find, value,
contains, count, and JSON pointers) with the parsed basic_json value.
A targeted test covers duplicates before and after edits that move the
object, in large objects with an index, in moved arrays, and in values
copied from other documents.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:16 +02:00
Niels Lohmann cb448406f6 Update the json_view banner and type_error.319 for editable documents
The banner still described a read-only view, and the documentation of
type_error.319 listed set and push_back only, although insert rejects
binary values as well.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:15 +02:00
Niels Lohmann 7d49247447 Replace a container by a scalar in constant time once it is linked
Replacing an array or object that spans several nodes by a scalar looks
up its parent from the root (find_parent), which is linear in the size
of the document: setting every element of a 20,000 element array took
more than half a second. The parent only has to switch to links once;
afterward the extent of the replaced value no longer matters. Nodes that
an entry of a moved sequence links to are now marked (node_flags::linked),
and assign() skips the lookup for them.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:14 +02:00
Niels Lohmann 07d8536bf1 Set a null value below a pointer as basic_json does
set(json_pointer, value) turned a null parent into an object for every
last reference token, so "/a/0" and "/a/-" below {"a":null} made
{"a":{"0":1}}, where basic_json's operator[](json_pointer) makes an
array. A null parent now becomes an array for "-" and for digit tokens
(filled with nulls up to the index) and an object otherwise. An invalid
index is reported before the parent changes.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:13 +02:00
Niels Lohmann 2247b0b728 Allow the edit arena to grow up to 4 GiB - 1 bytes
append_text() doubled the capacity of the arena and rejected the result
if it exceeded 4 GiB, so that an arena of more than 2 GiB could not grow
even though the 32-bit offsets of nodes address 4 GiB - 1 bytes. The
capacity is now clamped to that limit (text_capacity()), and an append
is rejected only if the bytes themselves do not fit.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:13 +02:00
Niels Lohmann 07b2891eda Check strings copied from another document for valid UTF-8
An editable document only holds valid UTF-8, but copy_scalar() copied the
strings and keys of a view of another document unchecked. A document of
a weaker check (or a borrowed text that changed after parsing) could
therefore bring ill-formed UTF-8 into it. The copy is checked now, with
the error that dump() reports for the string; copies within the same
document stay unchecked.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:12 +02:00
Niels Lohmann aa695d683b Do not leave a half-assigned container when set_moved() throws
assign() rewrote the kind, length and extent of a slot before set_moved()
registered its new element sequence. set_moved() can throw
(std::bad_alloc from reserving the bookkeeping vectors) for a slot that
is not moved yet, which left a container without the moved flag that
showed its old children. The bookkeeping is now reserved first
(reserve_moved()), so that nothing after the first write to the slot can
throw. block_of() reserves before it marks anything for the same reason.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:11 +02:00
Niels Lohmann d361cff07a Copy nested values into a document without recursion
Counting and copying the nodes of a view or a basic_json value into an
editable document recursed once per nesting level, so that a deeply
nested value overflowed the stack. The four functions now walk the value
with an explicit stack, as materialize() does.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:10 +02:00
Niels Lohmann c5798e64b2 Fix old clang and MSVC C4127 in editable json documents
Value-initialize the const std::less in find_parent (clang 3.4/3.6 do not
implement DR 253), and test the Editable template argument through a
function to avoid MSVC C4127.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:09 +02:00
Niels Lohmann fd4a29e636 Add editable json_documents: set, push_back, insert, and erase
basic_json_document gets a second template parameter, Editable
(false by default), plus the aliases json_editable_document,
json_editable_view, ordered_json_editable_document and
ordered_json_editable_view.

Editable documents can change values and structure without
rewriting the source text: set()/push_back() on values, keys,
array indices and JSON pointers; insert() before an array
element; erase() of an object key, array index or JSON pointer.

New values and element sequences go into edit storage that the
document owns and never moves, so views keep referring to their
value across edits and a parsed node never moves. Read-only
documents walk the plain node array and are unaffected.

Strings are checked for UTF-8 on entry, so dump() of an editable
document never throws type_error.316. Binary values cannot be
stored (type_error.319).

A seeded differential test applies random edits to an editable
document and to the equivalent ordered_json and compares both
after every step.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:08 +02:00
Niels Lohmann 2714283deb Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:06 +02:00
Niels Lohmann 369e348378 Move the dump, comparison, and large-object tests to unit-json_view_dump.cpp
The dump and comparison tests moved to their own file in the dump pull
request; the hash index tests of this branch join them there.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:05 +02:00
Niels Lohmann 231c7c1f2f Make json_view.hpp pass include-what-you-use
ci_single_binaries runs IWYU with --error on every header. For json_view.hpp
it suggested adding <array> (std::array is used), the headers that json.hpp
already provides (abi_config, abi_macros, input_adapters, json_pointer,
cpp_future, string_concat, value_t, json_fwd), and <version> for
std::nullptr_t, and removing <cstddef>.

- include <array>
- keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>)
- tell IWYU not to suggest the headers that json.hpp provides: the amalgamated
  json_view.hpp only includes json.hpp, so including them here would duplicate
  their definitions

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:04 +02:00
Niels Lohmann f04142b28a Index strings with size_t in the colliding-keys test (MSVC C4244 on Win32)
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:03 +02:00
Niels Lohmann 46be79d11c Avoid GCC useless-cast and strict-overflow warnings in unit-json_view.cpp
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:03 +02:00
Niels Lohmann 68898f12e4 Fix clang-tidy 22 findings in unit-json_view.cpp and unit-json_view_builder.cpp
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:02 +02:00
Niels Lohmann c7ff87b21f Fix clang-tidy 22 findings in the json_view headers
Silence bugprone-casting-through-void for the SSE loads (a reinterpret_cast
would trip -Wcast-align=strict), use auto for a cast initialiser, add
parentheses to a mixed expression, and name bugprone-std-namespace-modification
in the NOLINTs of the tuple_size/tuple_element specialisations.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:01 +02:00
Niels Lohmann ef070668b8 Keep the first of duplicate keys in the object hash index again
Lookups in objects with 128 members or more return the first member of a
repeated key again, like the linear search of smaller objects. This undoes
the code change of a69542046; its test now expects the first member from
lookups (with and without a table) and the last value from materialize()
and basic_json::parse().

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:45:00 +02:00
Niels Lohmann 556fdc75e2 Keep the last of duplicate keys in the object hash index
Lookups in objects with 128 members or more now return the last member of
a repeated key, like the linear search of smaller objects and like
materialize() and basic_json::parse(). build_object_index let the first
occurrence win, so the same text gave different results depending on the
size of the object.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:59 +02:00
Niels Lohmann ba811fc7bb Document the hash index number in node::extra
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:58 +02:00
Niels Lohmann 932ca7814f Use the portable string scan on non-x86 targets that define __SSE2__
WebAssembly with -msse2 defines __SSE2__, but has no <cpuid.h> or x86 intrinsics headers.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:57 +02:00
Niels Lohmann 8390420040 Release the spare capacity of the hash index in shrink_to_fit
shrink_to_fit() now trims the tables of large objects like the node array and the decoded strings, and the list of large objects is released as soon as the tables are built.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:56 +02:00
Niels Lohmann dbd773908f Bound the probe length of the large-object hash index
The key hash is not seeded, so keys chosen to collide made building the table quadratic (20,000 colliding keys took 470 ms to parse). A key may now sit at most 64 slots from its home slot; if a key would sit further away, the table is dropped and the object is searched linearly. Lookups stop after the same distance.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:56 +02:00
Niels Lohmann 02d4ede9b4 Remove an accidentally committed GCC module cache
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:55 +02:00
Niels Lohmann aeba45f128 Fix GCC module build and MSVC C4127 in the json_view SIMD code
GCC ignores the target attribute in modules, so the SSSE3 dispatch is
disabled for the module interface (the check stays portable, SSE2 is kept).
Make the 8-vs-16 byte unrolling condition in scan_string_run a
preprocessor/template split to avoid a constant condition (C4127).

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:54 +02:00
Niels Lohmann 59694a5e3e Scan json_view strings with SIMD and index large objects
Speed up json_view's parser with SIMD scanning and a hash table
for large objects.

Long runs of string bytes are scanned 16 bytes at a time with NEON
(AArch64, GCC and Clang) and SSE2 (x86-64), both baseline
instruction sets. Keys keep 16 table checks before the vector
loop, because their lengths repeat from record to record; string
values get 8, because their lengths vary more. Non-ASCII text is
validated 16 bytes at a time with simdjson's "lookup4" check
(Keiser and Lemire, 2021), with NEON on AArch64 and, on x86-64,
with SSSE3. SSSE3 is not part of baseline x86-64, so the check is
compiled for SSSE3 with a function attribute and used only where
CPUID reports it, which all x86-64 CPUs since about 2011 do; the
answer is cached in a statically initialized atomic, so there is
no guard of a local static and no global constructor. The same
input is accepted either way. JSON_VIEW_NO_SIMD selects the
portable code.

On x86-64, string runs are now checked vector-first: one SSE2
compare from the first byte finds the end of most keys and short
values, instead of a branch per byte for the first 8-16 bytes.
AArch64 keeps the byte-wise steps, where a NEON mask costs more and
the branches predict well. Entering an object or array no longer
stalls: open() stores the parent's frame field by field instead of
building it on the stack and reading it back with wider loads,
which waited for the narrower stores to retire.

Objects with 128 members or more get an open-addressing hash table
built when the object closes, so operator[], at(), find(),
contains(), count(), value(), and JSON pointers take constant time
on average in such objects; of duplicate keys, the first is kept,
as for the linear search. The idea comes from Boost.JSON.

simdjson is credited in simd.hpp's SPDX block, the README, and
license.md.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:53 +02:00
Niels Lohmann b92242d2e7 Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:51 +02:00
Niels Lohmann 078cfa95d4 Make json_view.hpp pass include-what-you-use
ci_single_binaries runs IWYU with --error on every header. For json_view.hpp
it suggested adding <array> (std::array is used), the headers that json.hpp
already provides (abi_config, abi_macros, input_adapters, json_pointer,
cpp_future, string_concat, value_t, json_fwd), and <version> for
std::nullptr_t, and removing <cstddef>.

- include <array>
- keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>)
- tell IWYU not to suggest the headers that json.hpp provides: the amalgamated
  json_view.hpp only includes json.hpp, so including them here would duplicate
  their definitions

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:50 +02:00
Niels Lohmann 5770d02a78 Split the dump and comparison tests off unit-json_view.cpp
The MinGW linker of the Windows clang jobs cannot link object files with more
than 32767 sections ("relocation truncated to fit: IMAGE_REL_AMD64_REL32
against `.rdata'"). unit-json_view.cpp reaches that limit as the stack
grows, so its "json_view dump" and "json_view comparison" test cases move
into unit-json_view_dump.cpp. The test generator and has_duplicate_keys()
that both files use move into json_view_test_helpers.hpp.

The new file mentions JSON_HAS_CPP_17, so it is built for C++17 like the file
it was split from.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:49 +02:00
Niels Lohmann 74301297c8 Fix the clang-tidy 22 findings in json_view and its tests
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:48 +02:00
Niels Lohmann 95c4044c52 Document and test first-wins lookups next to dump() and ==
dump() writes every member and == resolves duplicate keys as parse()
does, whereas lookups find the first member of a duplicate key.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:47 +02:00
Niels Lohmann 4edf9bca4a Do not shrink the output of dump()
finish() copied the whole output when the buffer was more than twice as
large as the result (citm dump +11%). The tighter source_extent()
estimate already keeps the buffer of a small value small.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:46 +02:00
Niels Lohmann ab0d330468 Hold the documents of the dump and comparison tests in names
root() of a temporary document is deleted: its views would dangle.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:45 +02:00
Niels Lohmann a431c030b0 Size the dump buffer of a small value by its own extent
The source extent of a value was read from the next node, falling back to the rest of the document when that node held a decoded string. dump() of a small value could thus allocate a buffer as large as the document. Skip a few such nodes, cap the fallback estimate, and shrink a buffer that is much larger than its output.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:45 +02:00
Niels Lohmann 20d7b21b76 Avoid raw string with escapes inside CHECK macro (MSVC C2017)
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:44 +02:00
Niels Lohmann 05fea2e972 Add dump() and comparisons to json_view
Add basic_json_view::dump() and the comparison operators, and read
floats from the parser's digit layout instead of rescanning the
token.

dump(indent, indent_char, ensure_ascii, number_format) writes a
value the way ordered_json::parse(text).dump() writes it for the
same arguments: members in document order, all of them should a
key occur more than once; strings escaped by the same rules, using
the library's scanning kernels; floats written with the library's
to_chars conversion, so the output equals basic_json's byte for
byte; integers copied from the source, where they are already
canonical, except -0, which parse() reads as 0. There is no
error_handler argument, because the view only holds valid UTF-8.
number_format::source copies numbers exactly as they appear in the
source (e.g. "1.50", "1E2", "-0"), which basic_json cannot provide.
operator<< takes the indentation from the stream width, as for
basic_json. The writer walks iteratively, so nesting depth is
limited by memory only.

operator== and operator!= compare two views, or a view and a
basic_json value in either order, by the rules basic_json's
operator== uses: numbers compare by value across their types,
objects compare by their members with duplicate keys resolved as
parse() resolves them, member order matters only where the object
type keeps one, and discarded views compare as discarded basic_json
values do, including under JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON.
Nothing is materialized except single scalars.

While parsing, the view now records where the integer digits, the
fraction digits, and the exponent of a float token are, so floats
and doubles with at most 19 digits are read from that layout with
the library's decimal_to_float() instead of rescanning the token.
Both round correctly, so the values are those of parse(). get<double>(),
materialize(), dump(), and the comparisons all use it.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:43 +02:00
Niels Lohmann d1d0e303a0 Report one-character non-numeric array indices like basic_json in the view
Develop's #5800 made basic_json report a JSON pointer array index such as
"/a" as parse_error.109 instead of out_of_range.404, as longer ones were;
the view's array_index() follows, with "-" and the empty token still
unresolved.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 12:44:42 +02:00
Niels Lohmann 7f3ba5a5bc Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:42 +02:00
Niels Lohmann 51ad02a5a1 Fix the clang-tidy 22 findings in json_view and its tests
The same changes as on the dump branch, where they were first made, so
that this branch passes clang-tidy on its own.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:41 +02:00
Niels Lohmann 7d475ebdc2 Make json_view.hpp pass include-what-you-use
ci_single_binaries runs IWYU with --error on every header. For json_view.hpp
it suggested adding <array> (std::array is used), the headers that json.hpp
already provides (abi_config, abi_macros, input_adapters, json_pointer,
cpp_future, string_concat, value_t, json_fwd), and <version> for
std::nullptr_t, and removing <cstddef>.

- include <array>
- keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>)
- tell IWYU not to suggest the headers that json.hpp provides: the amalgamated
  json_view.hpp only includes json.hpp, so including them here would duplicate
  their definitions

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:41 +02:00
Niels Lohmann d1570b9684 Avoid GCC useless-cast warnings in the integer index tests
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:40 +02:00
Niels Lohmann b8529ce4f2 Make json_view.hpp pass include-what-you-use
Mark the includes that are needed by design (json.hpp, the macro
unscope, <tuple> for the tuple_size specialization), take size_t from
<cstring>, and drop the forward declaration of basic_json_document that
the friend declaration makes redundant.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:39 +02:00
Niels Lohmann c5f8e31bd5 Do not force-inline the view's functions on MSVC
__forceinline makes MSVC report C4714 for function templates it cannot
inline (get<std::string>), an error under /WX. The forced inlining is
only a performance hint, so use plain inline there.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:38 +02:00
Niels Lohmann 386a06b59c Return the first member of duplicate keys from lookups again
Looking up the last member of a duplicate key cannot stop at a match, so
every lookup scanned the whole object (1.6 to 3.4 times slower for small
objects). operator[](key), at, find, value, contains, count, and JSON
pointer resolution return the first member again, as yyjson and simdjson
do; materialize() and get<map>() keep the last value, as parse().

The documentation says so in the feature page and on each lookup page,
and explains how to get the value parse() would give. The integer index
templates and the discarded chaining of operator[] stay.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:37 +02:00
Niels Lohmann ac1764b33a Test discarded views with is_discarded() in the operator[] docs and examples
The explicit conversion to bool of basic_json_view is gone.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:36 +02:00
Niels Lohmann e6610e16e6 Use named documents in the json_view tests that called root() on a temporary
root() of an rvalue document is deleted, because the views would dangle.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:35 +02:00
Niels Lohmann 4ef9ca592c Replace the removed operator bool of basic_json_view in the header and its tests
A view is tested with is_discarded(); the lookups in at(), value() and
contains(json_pointer) and the unit tests no longer rely on the explicit
conversion to bool.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:34 +02:00
Niels Lohmann 0eaea7ccba Make view lookups last-wins and chained access safe
* Lookups (operator[], at, find, contains, count, value, JSON pointers)
  return the last member of a duplicate key, as materialize() and
  parse() keep it.
* operator[] on a discarded view returns a discarded view instead of
  throwing, so v["a"]["b"] is safe for a missing "a".
* operator[] and at() take any integer type (not only int and size_t),
  fixing ambiguous calls with unsigned, long, std::int64_t, ...
* Fix the operator[] documentation, which claimed a discarded view for
  a type mismatch where type_error.305 is thrown.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:34 +02:00
Niels Lohmann e8907a55dc Add element access, iteration, values, and JSON pointers to json_view
Give basic_json_view the read-only access functions of basic_json:
operator[] and at() with keys and indices, front()/back(), find(),
contains(), count(), begin()/end() and cbegin()/cend(), items()
with structured bindings from C++17 on, and type_name().

Exceptions have the ids and messages of the const functions of
basic_json. Where basic_json has undefined behavior the view
answers safely: operator[] with a missing key or an out-of-range
index returns a discarded view, and front()/back() of an empty
container throw invalid_iterator.214. Objects are iterated in
document order, and all members are visited; duplicate-key lookups
find the first member (as yyjson and simdjson do), while parse(),
materialize(), and the map conversions keep the last value, as
parse() does. Keys of up to 16 bytes are compared with two
overlapping loads.

Add value conversions: get<T>()/get_to() for arithmetic types,
bool, nullptr_t, strings (std::basic_string copied,
string_view_t without a copy), BasicJsonType, views, std::vector,
and maps with string keys; get_string() for the string without a
copy; number_token() for the number exactly as written in the
source; value() with keys and JSON pointers; and operator[]/at()/
contains() with JSON pointers. Everything else, including types
with from_json(), goes through materialize() of that subtree.
get<T>() of arithmetic types is inlined down to the conversion, so
reading an integer needs no call.

detail::json_pointer_access exposes a pointer's reference tokens
to code outside basic_json.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:33 +02:00
Niels Lohmann ae33774146 Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:30 +02:00
Niels Lohmann e9716d3d3d Silence a clang-tidy use-after-move finding in the json_view test
const_text is const, so std::move does not move from it; the second call
is part of the const rvalue test.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:30 +02:00
Niels Lohmann 2491be2a64 Read the node array base after emit() in the view builder's open()
emit() moves the node array when it grows, and the subtraction read base
in the same expression, so the order was unspecified. MSVC Release builds
without forced inlining read the old base; the container index then
pointed outside the array and close() wrote out of bounds.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:29 +02:00
Niels Lohmann f9b45bc087 Make json_view.hpp pass include-what-you-use
ci_single_binaries runs IWYU with --error on every header. For json_view.hpp
it suggested adding <array> (std::array is used), the headers that json.hpp
already provides (abi_config, abi_macros, input_adapters, json_pointer,
cpp_future, string_concat, value_t, json_fwd), and <version> for
std::nullptr_t, and removing <cstddef>.

- include <array>
- keep <cstddef> (nullptr_t, size_t; IWYU attributes them to <version> and <cstring>)
- tell IWYU not to suggest the headers that json.hpp provides: the amalgamated
  json_view.hpp only includes json.hpp, so including them here would duplicate
  their definitions
- export json.hpp, keep macro_unscope.hpp, and drop the unused forward declaration of the document class

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:28 +02:00
Niels Lohmann 009eb71a47 Make max_input_size a function (GCC -Wunused-const-variable)
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:27 +02:00
Niels Lohmann 38f5c0cc69 Check the steps of the deep-nesting test separately
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:26 +02:00
Niels Lohmann 0000cccf0b Suppress Flawfinder's read() finding on the deleted overload
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:25 +02:00
Niels Lohmann bb17f8a324 Annotate intentional patterns in unit-json_view.cpp for clang-tidy
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:24 +02:00
Niels Lohmann f5710b21b5 Fix clang-tidy findings in unit-json_view_builder.cpp
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:24 +02:00
Niels Lohmann e084f69357 Give document_data a user-provided constructor
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:23 +02:00
Niels Lohmann a491a9137b Fuzz json_document with exact-size buffers and parse options
The fuzzer only parsed a std::string with default options. Also parse an
exact-size byte vector, which has no NUL after its last byte and takes the
bounds-checked path, and derive ignore_comments and ignore_trailing_commas
from the first input byte, comparing against json::parse and json::accept
with the same options.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:22 +02:00
Niels Lohmann aed12fbad2 Align the banner comment of json_view.hpp
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:21 +02:00
Niels Lohmann 1d7c9125a3 Remove the unused legacy_discarded_value_comparison from abi_config
Nothing reads it: the view does not compare values.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:20 +02:00
Niels Lohmann 20d76ebf87 State the exact input size limit of json_document
The check rejects inputs of 0xFFFFFFF0 bytes or more, but the exception
message and the documentation said 4 GiB. Name the limit once
(max_input_size), and state 4 GiB minus 16 bytes in the message and the
documentation. Test the limit with a container that only claims the size.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:19 +02:00
Niels Lohmann f2fa7ea661 Check the node array size for overflow
reserve(n) and the growth of the index computed n * sizeof(node) without a
check, which wraps around on 32-bit targets for inputs of about 1 GiB and
allocates a too small array. Throw std::bad_alloc for a count beyond the
address space and clamp the growth step to it.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:18 +02:00
Niels Lohmann 2a55c9065b Store node integers by halves on big-endian targets
The non-little-endian path of the node writer wrote the integer's native
word over len and next, so len got the high half there. Compose and split
the value explicitly (len is the low half, next the high half); the
little-endian path stays a plain memcpy.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:17 +02:00
Niels Lohmann b26a898619 Delete json_document::root() on temporary documents
auto v = json_document::parse(text).root() compiled and left the view
dangling. Delete the overload for rvalue documents, take a named document
in the tests, and document the lifetime rule.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:17 +02:00
Niels Lohmann 2d1f109f8b Remove the conversion to bool from json_view
explicit operator bool meant "refers to a value", which silently differs
from what a basic_json converts to. Use !v.is_discarded() instead.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:16 +02:00
Niels Lohmann 882675320b Copy const rvalue strings and document the accepted inputs
json_document::parse(std::move(const_string)) failed to compile with
"no matching read_kind": only a non-const rvalue std::string can be moved
from. Treat a const rvalue as a copied byte container.

parse() does not accept everything BasicJsonType::parse() does: a FILE*
and pointers to or arrays of wide characters are rejected at compile time.
List the supported inputs instead.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:15 +02:00
Niels Lohmann d449861523 Reject integer lengths in json_document::parse
parse(ptr, len) compiled: len converted to allow_exceptions, and ptr was
read as a C string, past the end of a buffer without a terminating NUL.
Delete the overloads of parse, parse_copy, accept, and read that take an
integer other than bool where the flags are expected.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:14 +02:00
Niels Lohmann 54528c28c2 Exclude libstdc++'s string_view comparison from the sign-change check
basic_string_view::_S_compare stores the difference of two lengths in a
signed difference_type on purpose, which -fsanitize=integer reports for
every comparison with a shorter view (test-json_view_cpp17).

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:13 +02:00
Niels Lohmann adb623649b Fix document_data for old Clang (3.4-3.6)
Drop the empty braced NSDMIs of the std::string members: old Clang
rejects the defaulted constructor when it is used by a member
initializer before the end of the class definition.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:12 +02:00
Niels Lohmann 5bc36a6947 Add json_document and json_view: node index, parser, and document
Add json_document and json_view, a read-only, zero-copy index of a
JSON text, as the first public slice of the zero-copy view (#5295).

A parse produces a flat array of 16-byte nodes in document order,
one per value and one per object key. Strings stay in the source
text; escaped strings are decoded into an arena. Integers are
converted while their digits are in the cache; floats keep only
their digit layout and are converted on read. Containers store the
size of their subtree, so a reader can step over one in constant
time. A document makes a handful of allocations, however many
values it has.

The parser accepts exactly what json::parse accepts, with every
combination of ignore_comments and ignore_trailing_commas, with and
without a trailing NUL, and under JSON_STRICT_NUL_HANDLING. It is
portable C++11 and does not depend on byte order.

basic_json_document adds parse, parse_copy, accept, read (reuses a
document's memory), root, is_discarded, source, owns_source,
node_count, memory_usage, and shrink_to_fit. basic_json_view adds
type, the is_* queries, operator bool, size, empty, materialize,
and source_offset. A parse error throws the same exception
basic_json::parse would throw for the same input, message and
position included.

detail::abi_config keeps JSON_STRICT_NUL_HANDLING and
JSON_USE_LEGACY_DISCARDED_VALUE_COMPARISON readable after json.hpp
undefines them, in the ABI namespace so they always match the
basic_json in use.

A NUL byte that ends a // comment is the end of the input, as in
parse() since #5696.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:11 +02:00
Niels Lohmann 05e11ce350 Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:09 +02:00
Niels Lohmann 087885f142 Silence MSVC C4127 for a platform-constant check in the to_chars test
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:08 +02:00
Niels Lohmann dc01cc02e2 Credit Zmij's authors in to_chars.hpp, the README, and the license page
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:07 +02:00
Niels Lohmann 007dfb0742 Select the Zmij conversion by a trait, not by the double overload
The non-template overloads for double asserted binary64 doubles wherever json.hpp was included, so the library no longer compiled where double is not IEEE 754 binary64 (AVR, -fshort-double). A trait now picks Zmij for any binary64 type, including a long double of that format (MSVC, Apple Arm), and Grisu2 for the others. Remove the unused write_short_decimal, powers_of_ten_16, zmij::decimal, zmij::to_decimal, and shortest_digits(double).

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:07 +02:00
Niels Lohmann a44c80c6ce Fix CI findings in the Zmij writer and its tests
- bit_ops.hpp: include macro_scope.hpp (JSON_HEDLEY_ALWAYS_INLINE); fixes IWYU
- to_chars.hpp: C4100 for the unused parameter in release builds, clang-tidy
  sign comparison, cpplint runtime/int, GCC -Wstrict-overflow (unsigned abs)
- unit-to_chars.cpp: parse with the library instead of strtod (MinGW's strtod
  rounds some 16/17 digit inputs wrongly); no floating-point std::to_chars
  with icpc

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:06 +02:00
Niels Lohmann f6895fb84e Write doubles with the shortest digits (Żmij), digits in registers
Write doubles with the conversion of Zmij by Victor Zverovich (MIT),
ported to C++11 (detail/conversions/zmij.hpp). It finds the
shortest decimal that reads back as the same double, and the
closest one if there are several. Grisu2, used until now, is fast
but not always shortest: it sometimes writes a 17th digit where 16
suffice, or a last digit that is not the closest. The layout is
unchanged (1.5, 100.0, 1e+100, -0.0); float keeps Grisu2.

Digits are converted eight at a time with the BCD conversion of
Xiang JunBo, as in Zmij, and written with one byte swap per eight
digits and fixed-size moves instead of per-digit loops. Leading and
trailing zeros are counted from those bytes. to_chars() uses a
local buffer when the caller's is shorter than the 41 bytes this
may write. The powers of ten come from the number-parsing table,
adjusted where it holds values rounded up, and extended with Zmij's
compressed tables beyond 10^308.

write_shortest() converts its 16 digits in one vector register
(SSE2 on x86-64, NEON on 64-bit Arm, both baseline) and inserts the
decimal point inside the register, avoiding a store-forwarding
stall that cost about 25% of the time to write a double. dump()
writes floats and integers straight into the serializer's write
buffer instead of copying them from a member buffer, and small
integers eight digits at a time. read_eight_bytes() and
parse_eight_digits() are marked always-inline, which GCC had been
calling out of line in the number-parsing loops.

Of one million random doubles, about 0.14% are now written with
different digits, always to a value that still reads back as the
same double.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:30:05 +02:00
Niels Lohmann 247b03b2de Regenerate the amalgamated headers
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:29:57 +02:00
Niels Lohmann 56ff716d88 Mark the unsigned long of the MSVC bit scans for cpplint
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:29:56 +02:00
Niels Lohmann 9bbd0dafb0 Fix clang-tidy 22 findings in unit-class_lexer.cpp
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:29:55 +02:00
Niels Lohmann 1c8437a724 Reword float conversion notes for the string type and number_float_t docs
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:29:54 +02:00
Niels Lohmann 934f6644d7 Load string scan words with memcpy and use MSVC bit-scan intrinsics
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:29:53 +02:00
Niels Lohmann 1795f59f10 Fix CI warnings in own float parser
- pow5_table.hpp: pow5_128_largest_power was unused in this branch's
  own code (GCC -Werror=unused-const-variable); tie it to the table
  size with a static_assert instead of removing it, since a later
  branch in the stack (json-view/23-zmij) uses it.
- number_parse.hpp: rename the local variable `copy` to `buffer` to
  satisfy cpplint's build/include_what_you_use check.
- unit-class_lexer.cpp: extend the NOLINT list on the seeded mt19937
  with bugprone-random-generator-seed, and parenthesize
  `8 * sizeof(Bits) - 1` for clang-tidy.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:29:53 +02:00
Niels Lohmann 2434cb6e72 Speed up the lexer: own float parser, string scan, and \u table
Give the library its own correctly rounded float converter for
binary32 and binary64 (IEEE 754), and speed up the lexer's string
and escape scanning.

The converter splits a number token into sign, significand, and
decimal exponent, then tries Clinger's fast path, then a templated
Eisel-Lemire step, and falls back to an exact big-integer digit
comparison for tokens with more than 19 significant digits whose two
candidate values round differently. This replaces std::from_chars
and strtod/strtof for both formats, so parsed values no longer
depend on the C/C++ library or the current locale. The strtold
fallback kept for other long double formats (x87, binary128) now
also copies a multi-byte decimal point correctly, fixing #5660.
eisel_lemire() and decimal_to_float() are always inlined so callers
keep the whole conversion in their hot loop.

The string-scanning kernels in string_scan.hpp find a stop byte with
the trailing-zero count of the SWAR mask instead of a byte loop, and
scalar_string_bulk_run() validates a run of multi-byte UTF-8
sequences one after another instead of re-searching after each one.

get_codepoint() decodes a contiguous \uXXXX escape with one table
lookup per byte instead of four range-checked get() calls; the
streaming path and all error positions are unchanged.

Adds 508 generated hard float-parsing cases with expected binary32
and binary64 bits, and kernel-comparison tests for the string scans
and the escape table against byte-by-byte references.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>
2026-10-11 11:29:52 +02:00
1017 changed files with 46315 additions and 60678 deletions

No files matched your search

+7 -36
View File
@@ -1,33 +1,3 @@
# Style or vendor rule sets that do not fit a header-only library:
# altera-*, fuchsia-*, llvmlibc-*, android-cloexec-fopen, boost-use-ranges, llvm-header-guard,
# llvm-include-order, llvm-prefer-static-over-anonymous-namespace, llvm-use-ranges,
# misc-use-anonymous-namespace, google-runtime-float, google-runtime-int, hicpp-signed-bitwise,
# bugprone-signed-bitwise, hicpp-explicit-conversions, google-explicit-constructor,
# cppcoreguidelines-explicit-constructor, misc-explicit-constructor (implicit conversions are the
# API), readability-trailing-comma,
# hicpp-avoid-goto / cppcoreguidelines-avoid-goto, hicpp-no-array-decay,
# hicpp-uppercase-literal-suffix, readability-uppercase-literal-suffix, modernize-use-trailing-return-type.
# Constructs the library needs on purpose (the library supports C++11 and legacy compilers):
# cppcoreguidelines-macro-usage, cppcoreguidelines-avoid-do-while (macros),
# cppcoreguidelines-pro-bounds-*, cppcoreguidelines-pro-type-reinterpret-cast,
# cppcoreguidelines-pro-type-union-access (parsers, serializers, basic_json's value union),
# cppcoreguidelines-avoid-const-or-ref-data-members, cppcoreguidelines-rvalue-reference-param-not-moved,
# cppcoreguidelines-avoid-non-const-global-variables, misc-non-private-member-variables-in-classes,
# misc-no-recursion (value walks are recursive, bounded by detail::recursion_depth_limit()),
# modernize-type-traits, modernize-use-constraints, modernize-use-ranges, modernize-use-std-numbers,
# modernize-use-designated-initializers, modernize-use-nodiscard, modernize-concat-nested-namespaces,
# readability-redundant-typename, readability-redundant-parentheses,
# readability-redundant-access-specifiers, readability-simplify-boolean-expr,
# readability-use-concise-preprocessor-directives, modernize-use-string-view,
# modernize-use-integer-sign-comparison (needs std::cmp_less; the flagged
# static_cast<std::size_t>(end - pos) < n comparisons are deliberate)
# (all need a newer standard or compiler than C++11, or would change macro-generated or
# deliberately explicit code).
# Too noisy to be useful (numeric parsing/formatting code, doctest, tests):
# bugprone-easily-swappable-parameters, cppcoreguidelines-avoid-magic-numbers, readability-magic-numbers,
# readability-identifier-length, readability-function-cognitive-complexity, performance-enum-size,
# concurrency-mt-unsafe, misc-confusable-identifiers, misc-include-cleaner (run on its own for
# the consumer headers in cmake/ci.cmake).
# portability-avoid-pragma-once: kept disabled on purpose. #pragma once is accepted
# by every supported compiler, and tools/amalgamate/amalgamate.py strips it from
# single_include, so there is nothing left to fix here.
@@ -40,14 +10,14 @@ Checks: '*,
-android-cloexec-fopen,
-boost-use-ranges,
-bugprone-easily-swappable-parameters,
-bugprone-signed-bitwise,
-cert-err58-cpp,
-clang-analyzer-webkit.NoUncountedMemberChecker,
-concurrency-mt-unsafe,
-cppcoreguidelines-avoid-const-or-ref-data-members,
-cppcoreguidelines-avoid-do-while,
-cppcoreguidelines-avoid-goto,
-cppcoreguidelines-avoid-magic-numbers,
-cppcoreguidelines-avoid-non-const-global-variables,
-cppcoreguidelines-explicit-constructor,
-cppcoreguidelines-macro-usage,
-cppcoreguidelines-pro-bounds-avoid-unchecked-container-access,
-cppcoreguidelines-pro-bounds-array-to-pointer-decay,
@@ -56,15 +26,19 @@ Checks: '*,
-cppcoreguidelines-pro-type-reinterpret-cast,
-cppcoreguidelines-pro-type-union-access,
-cppcoreguidelines-rvalue-reference-param-not-moved,
-cppcoreguidelines-virtual-class-destructor,
-fuchsia-default-arguments-calls,
-fuchsia-default-arguments-declarations,
-fuchsia-overloaded-operator,
-google-explicit-constructor,
-google-readability-function-size,
-google-runtime-float,
-google-runtime-int,
-hicpp-avoid-goto,
-hicpp-explicit-conversions,
-hicpp-function-size,
-hicpp-no-array-decay,
-hicpp-no-assembler,
-hicpp-signed-bitwise,
-hicpp-uppercase-literal-suffix,
-llvm-header-guard,
@@ -74,7 +48,6 @@ Checks: '*,
-llvmlibc-*,
-misc-use-anonymous-namespace,
-misc-confusable-identifiers,
-misc-explicit-constructor,
-misc-include-cleaner,
-misc-no-recursion,
-misc-non-private-member-variables-in-classes,
@@ -82,22 +55,20 @@ Checks: '*,
-modernize-type-traits,
-modernize-use-constraints,
-modernize-use-designated-initializers,
-modernize-use-integer-sign-comparison,
-modernize-use-nodiscard,
-modernize-use-ranges,
-modernize-use-string-view,
-modernize-use-std-numbers,
-modernize-use-trailing-return-type,
-performance-enum-size,
-portability-avoid-pragma-once,
-readability-function-cognitive-complexity,
-readability-function-size,
-readability-identifier-length,
-readability-magic-numbers,
-readability-redundant-access-specifiers,
-readability-redundant-parentheses,
-readability-redundant-typename,
-readability-simplify-boolean-expr,
-readability-trailing-comma,
-readability-uppercase-literal-suffix,
-readability-use-concise-preprocessor-directives'
+2 -9
View File
@@ -18,8 +18,7 @@ environment:
matrix:
# The Visual Studio 2017 jobs compile everything with /std:c++17, so they
# only build the C++17 variant of each test, split into two jobs each to
# stay below AppVeyor's 60-minute limit per job. The Visual Studio 2019
# job builds the tests for all standards and is split for the same reason.
# stay below AppVeyor's 60-minute limit per job.
- APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
configuration: Debug
platform: x86
@@ -51,13 +50,7 @@ environment:
configuration: Release
platform: x86
CXX_FLAGS: "/W4 /WX"
CMAKE_OPTIONS: "-DJSON_ImplicitConversions=OFF -DJSON_TestShard=0/2"
GENERATOR: Visual Studio 16 2019
- APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2019
configuration: Release
platform: x86
CXX_FLAGS: "/W4 /WX"
CMAKE_OPTIONS: "-DJSON_ImplicitConversions=OFF -DJSON_TestShard=1/2"
CMAKE_OPTIONS: "-DJSON_ImplicitConversions=OFF"
GENERATOR: Visual Studio 16 2019
- APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
+1 -1
View File
@@ -28,7 +28,7 @@ jobs:
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
+20 -41
View File
@@ -22,7 +22,7 @@ jobs:
runs-on: ubuntu-latest
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -31,13 +31,13 @@ jobs:
mkdir -p ./pr
echo ${{ github.event.number }} > ./pr/number
echo ${{ github.event.pull_request.user.login }} > ./pr/author
- uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
- uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
with:
name: pr
path: pr/
check:
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
env:
MAIN_DIR: ${{ github.workspace }}/main
INCLUDE_DIR: ${{ github.workspace }}/main/single_include/nlohmann
@@ -46,7 +46,7 @@ jobs:
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -77,12 +77,13 @@ jobs:
cd $MAIN_DIR
# Built from this PR's own tools/macro_builder/main.cpp, not a
# develop checkout: unlike amalgamate.py, this tool has no other
# source of truth to check against (its own README documents that
# it must reproduce macro_scope.hpp byte for byte), so there is
# nothing to gain from checking out a separate copy, and doing so
# would make this step fail on a PR that adds support for a new
# dispatch table until that PR itself merges to develop.
# develop checkout: unlike amalgamate.py and generate_natvis.py,
# this tool has no other source of truth to check against (its
# own README documents that it must reproduce macro_scope.hpp
# byte for byte), so there is nothing to gain from checking out a
# separate copy, and doing so would make this step fail on a PR
# that adds support for a new dispatch table until that PR itself
# merges to develop.
TMPDIR=$(mktemp -d ./macro_builder_check.XXXXXX)
c++ -std=c++11 tools/macro_builder/main.cpp -o "$TMPDIR/macro_builder"
"$TMPDIR/macro_builder" > "$TMPDIR/paste.hpp"
@@ -145,36 +146,14 @@ jobs:
- name: Regenerate nlohmann_json.natvis
run: |
cd $MAIN_DIR
# The generator and its template are what this check verifies the
# committed natvis file against (which namespaces it lists, and
# what each entry looks like), so run this PR's copy rather than
# the develop checkout's: with develop's, a PR that changes either
# could never pass. generate_natvis.py loads the template from its
# own directory. Like the macro_builder step above, this only runs
# PR content in a job without credentials.
python3 tools/generate_natvis/generate_natvis.py $MAIN_DIR
- name: Check the nlohmann_json.natvis generator options
run: |
cd $MAIN_DIR
# The options for configurations outside the checked-in file write
# to a temporary file, so they do not affect the diff below.
GENERATOR=tools/generate_natvis/generate_natvis.py
python3 $GENERATOR --list-tags
TAG_COUNT=$(python3 $GENERATOR --list-tags | wc -l)
python3 $GENERATOR --abi-tags diag,_dp,_ns --abi-tags _diag --output $RUNNER_TEMP/abi_tags.natvis
grep -q '<!-- Namespace nlohmann::json_abi_diag_dp_ns -->' $RUNNER_TEMP/abi_tags.natvis
grep -q '<!-- Namespace nlohmann::json_abi_diag_dp_ns_v[0-9_]* -->' $RUNNER_TEMP/abi_tags.natvis
test $(grep -c '<!-- Namespace ' $RUNNER_TEMP/abi_tags.natvis) -eq $(( $(grep -c '<!-- Namespace ' nlohmann_json.natvis) + 2 ))
python3 $GENERATOR --all --output $RUNNER_TEMP/all.natvis
test $(grep -c '<!-- Namespace ' $RUNNER_TEMP/all.natvis) -eq $(( (1 << TAG_COUNT) * 2 + 1 ))
if python3 $GENERATOR --abi-tags _unknown --output $RUNNER_TEMP/unknown.natvis; then
echo "generate_natvis.py accepted an unknown ABI tag"
exit 1
fi
# The template is what this check verifies the committed natvis
# file against, so take it from this PR rather than from the
# develop checkout: generate_natvis.py loads the template from its
# own directory, and with develop's copy a PR that changes the
# template could never pass. Like the macro_builder step above,
# this only renders PR content in a job without credentials.
cp tools/generate_natvis/nlohmann_json.natvis.j2 $NATVIS_TOOL_DIR/
python3 $NATVIS_TOOL_DIR/generate_natvis.py $MAIN_DIR
- name: Build patch and check for differences
id: diff
@@ -194,7 +173,7 @@ jobs:
# instead of installing the pinned astyle version locally.
- name: Upload patch
if: steps.diff.outputs.has_diff == 'true'
uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
with:
name: amalgamation-patch
path: patch/amalgamation.patch
+1 -1
View File
@@ -20,7 +20,7 @@ jobs:
timeout-minutes: 30
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
+2 -2
View File
@@ -13,7 +13,7 @@ jobs:
runs-on: ubuntu-22.04
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -35,7 +35,7 @@ jobs:
dry-run: false
language: c++
- name: Upload Crash
uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
if: failure() && steps.build.outcome == 'success'
with:
name: artifacts
+5 -5
View File
@@ -21,13 +21,13 @@ permissions:
jobs:
CodeQL-Build:
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
permissions:
security-events: write
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -38,14 +38,14 @@ jobs:
# Initializes the CodeQL tools for scanning.
- name: Initialize CodeQL
uses: github/codeql-action/init@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
uses: github/codeql-action/init@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
with:
languages: c-cpp
# Autobuild attempts to build any compiled languages (C/C++, C#, or Java).
# If this step fails, then you should remove it and run the build manually (see below)
- name: Autobuild
uses: github/codeql-action/autobuild@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
uses: github/codeql-action/autobuild@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
- name: Perform CodeQL Analysis
uses: github/codeql-action/analyze@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
uses: github/codeql-action/analyze@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
@@ -20,7 +20,7 @@ jobs:
pull-requests: write
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -37,14 +37,6 @@ jobs:
var matchArtifact = artifacts.data.artifacts.filter((artifact) => {
return artifact.name == "pr"
})[0];
// a run that failed before its jobs started (e.g. a stale queued
// run cancelled long after its push) has no artifact to report on
if (!matchArtifact) {
core.notice('Run ${{ github.event.workflow_run.id }} has no "pr" artifact; nothing to comment on.');
core.setOutput('found', 'false');
return;
}
core.setOutput('found', 'true');
var download = await github.rest.actions.downloadArtifact({
owner: context.repo.owner,
repo: context.repo.repo,
@@ -59,11 +51,9 @@ jobs:
# Extract the untrusted PR artifact into a dedicated empty directory and
# read only the two expected files by fixed path afterwards. This avoids a
# malicious archive overwriting workspace files or escaping via ../ paths.
- if: steps.download.outputs.found == 'true'
run: unzip -o pr.zip -d ./pr_artifact
- run: unzip -o pr.zip -d ./pr_artifact
- name: 'Comment on PR'
if: steps.download.outputs.found == 'true'
uses: actions/github-script@3a2844b7e9c422d3c10d287c895573f7108da1b3 # v9.0.0
with:
github-token: ${{ secrets.GITHUB_TOKEN }}
+1 -1
View File
@@ -21,7 +21,7 @@ jobs:
runs-on: ubuntu-latest
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
+3 -4
View File
@@ -31,7 +31,7 @@ jobs:
security-events: write
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -43,11 +43,10 @@ jobs:
- name: flawfinder_scan
uses: david-a-wheeler/flawfinder@c4216b74cf2639ffa98503768bd6e4299b5440c9 # v2.0.20
with:
# single_include/ is generated from include/ and would report every finding twice
arguments: "--sarif --exclude '*/single_include/*' ./"
arguments: '--sarif ./'
output: 'flawfinder_results.sarif'
- name: Upload analysis results to GitHub Security tab
uses: github/codeql-action/upload-sarif@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
uses: github/codeql-action/upload-sarif@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
with:
sarif_file: ${{github.workspace}}/flawfinder_results.sarif
+2 -2
View File
@@ -54,7 +54,7 @@ jobs:
timeout-minutes: 60
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -78,7 +78,7 @@ jobs:
- name: Summary
run: cat tests/benchmarks/json_view/results/*.md >> "$GITHUB_STEP_SUMMARY"
- uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
- uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
with:
name: json_view-benchmarks-${{ matrix.runner }}-${{ inputs.compiler || 'g++' }}
path: tests/benchmarks/json_view/results/
+1 -1
View File
@@ -23,7 +23,7 @@ jobs:
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
+1 -1
View File
@@ -37,7 +37,7 @@ jobs:
runs-on: ubuntu-latest
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
+4 -4
View File
@@ -40,7 +40,7 @@ jobs:
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -50,7 +50,7 @@ jobs:
persist-credentials: false
- name: "Run analysis"
uses: ossf/scorecard-action@fa7117db83c52d787ae5a89f350999701505d78e # v2.5.0
uses: ossf/scorecard-action@2d1146689b8cda280b9bc96326124645441f03bc # v2.4.4
with:
results_file: results.sarif
results_format: sarif
@@ -72,7 +72,7 @@ jobs:
# Upload the results as artifacts (optional). Commenting out will disable uploads of run results in SARIF
# format to the repository Actions tab.
- name: "Upload artifact"
uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
with:
name: SARIF file
path: results.sarif
@@ -80,6 +80,6 @@ jobs:
# Upload the results to GitHub's code scanning dashboard.
- name: "Upload to code-scanning"
uses: github/codeql-action/upload-sarif@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
uses: github/codeql-action/upload-sarif@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
with:
sarif_file: results.sarif
+3 -3
View File
@@ -33,10 +33,10 @@ jobs:
security-events: write # for github/codeql-action/upload-sarif to upload SARIF results
actions: read # only required for a private repository by github/codeql-action/upload-sarif to get the Action run status
name: Scan
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -65,7 +65,7 @@ jobs:
# Upload SARIF file generated in previous step
- name: Upload SARIF file
uses: github/codeql-action/upload-sarif@6f2ac81f5cd81fe351a197ba0b00d91d03cd2aee # v4.39.0
uses: github/codeql-action/upload-sarif@2892aa5e19bbd11bc0cff5427e3b750a04d9e3c2 # v4.38.2
with:
sarif_file: semgrep.sarif
if: always()
+1 -1
View File
@@ -16,7 +16,7 @@ jobs:
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
+32 -32
View File
@@ -25,20 +25,20 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
run: cmake --build build --target ci_test_gcc
ci_meson_install:
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
steps:
- uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Check that Meson and pkg-config offer the CMake options
run: make check_build_options
- name: Install Meson
@@ -77,10 +77,10 @@ jobs:
cmake --build build-import-split
ci_infer:
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -92,27 +92,27 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
run: cmake --build build --target ci_infer
- name: Archive Infer report
if: always()
uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
with:
name: infer-report
path: ${{ github.workspace }}/build/build_infer/infer-out/report.txt
if-no-files-found: ignore
ci_static_analysis_ubuntu:
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
strategy:
matrix:
target: [ci_test_single_header, ci_cppcheck, ci_cpplint, ci_reproducible_tests, ci_non_git_tests, ci_offline_testdata, ci_reuse_compliance, ci_test_valgrind]
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -123,7 +123,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
@@ -142,7 +142,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
@@ -168,17 +168,17 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
run: cmake --build build --target ${{ matrix.target }}
ci_test_coverage:
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -197,7 +197,7 @@ jobs:
- name: Build
run: cmake --build build --target ci_test_coverage
- name: Archive coverage report
uses: actions/upload-artifact@cf430e030ddbb5b0abf93d22962f4752f3646cd9 # v7.0.2
uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
with:
name: code-coverage-report
path: ${{ github.workspace }}/build/html
@@ -244,7 +244,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: CXX=g++-${{ matrix.compiler }} cmake -S . -B build -DJSON_CI=On
- name: Build
@@ -262,7 +262,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
@@ -279,7 +279,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Disable filesystem support (std::filesystem is unusable) for clang 7 / 8 / 9 / 10
run: echo "JSON_FORCED_GLOBAL_COMPILE_OPTIONS=-DJSON_HAS_FILESYSTEM=0;-DJSON_HAS_EXPERIMENTAL_FILESYSTEM=0" >> "$GITHUB_ENV"
if: ${{ matrix.compiler == '7' || matrix.compiler == '8' || matrix.compiler == '9' || matrix.compiler == '10' }}
@@ -299,7 +299,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
@@ -319,7 +319,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build with libc++
@@ -346,7 +346,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
@@ -366,7 +366,7 @@ jobs:
# import-std support. Its opt-in token is CMake-version-specific, so pin
# CMake to the version whose token is set in tests/module_cpp20/CMakeLists.txt.
- name: Get pinned CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
with:
cmakeVersion: 4.3.4
# Clang: the std library module is provided by libc++ (the image's libstdc++
@@ -392,7 +392,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
@@ -409,7 +409,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
@@ -423,17 +423,17 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DJSON_CI=On
- name: Build
run: cmake --build build --target ci_nvhpc
ci_emscripten:
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -443,20 +443,20 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Run CMake
run: cmake -S . -B build -DCMAKE_TOOLCHAIN_FILE=$EMSDK/upstream/emscripten/cmake/Modules/Platform/Emscripten.cmake -GNinja
- name: Build
run: cmake --build build
ci_test_documentation:
runs-on: ubuntu-26.04
runs-on: ubuntu-latest
strategy:
matrix:
target: [ci_test_examples, ci_test_build_documentation, ci_test_documentation_mermaid]
steps:
- name: Harden Runner
uses: step-security/harden-runner@ccd8616d44fd3846e67624a50d5aad6d37bf2d25 # v2.22.1
uses: step-security/harden-runner@e14015d583714f6e62063499dc959a02595150a1 # v2.21.1
with:
egress-policy: audit
@@ -465,7 +465,7 @@ jobs:
persist-credentials: false
# the git-revision-date-localized plugin needs the history; a shallow clone makes the strict build fail
fetch-depth: ${{ matrix.target == 'ci_test_build_documentation' && '0' || '1' }}
- uses: actions/setup-node@949feb2413d6458794dcd2491c4babbbce0c15c1 # v7.1.0
- uses: actions/setup-node@820762786026740c76f36085b0efc47a31fe5020 # v7.0.0
if: matrix.target == 'ci_test_documentation_mermaid'
with:
node-version: 24
@@ -484,7 +484,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Check that the job runs natively on arm64
run: uname -m && test "$(uname -m)" = aarch64
- name: Run CMake
+10 -12
View File
@@ -90,7 +90,7 @@ jobs:
with:
persist-credentials: false
- name: Get latest CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
- name: Set extra CXX_FLAGS for latest std_version
# /wd5285 silences C5285 emitted by the bundled third-party doctest.h, which
# specializes std::tuple (newly diagnosed by the VS2026 v145 toolset)
@@ -166,21 +166,19 @@ jobs:
# link, but the binaries clang 11.0.1 and clang 18.1.8 then produce crash
# before doctest prints its first line - 39 of 102 tests on clang 18.
# Keep the objects small by splitting the test files instead.
# The tests link with LLD: GNU ld fails on objects with more than 32767
# sections with "relocation truncated to fit: IMAGE_REL_AMD64_REL32
# against `.rdata'", as it stores the section an associative COMDAT
# section belongs to in 16 bits (x_associated in binutils'
# include/coff/internal.h) and so discards the jump tables of inline
# functions together with the wrong function. Each basic_json
# specialization and input type a test file instantiates adds many
# sections, so unit-msgpack.cpp and unit-regression2.cpp kept crossing
# that limit as the library grew.
# Objects with more than 65535 sections fail to link with "relocation
# truncated to fit: IMAGE_REL_AMD64_REL32 against `.rdata'": the MinGW
# linker stores the section an associative COMDAT section belongs to in
# 16 bits (x_associated in binutils' include/coff/internal.h), so it
# discards the jump tables of inline functions together with the wrong
# function. Each basic_json specialization a test file instantiates adds
# many sections, so test a second one in a file of its own.
- name: Run CMake
run: cmake -S . -B build ^
-DCMAKE_CXX_COMPILER="C:/Program Files/LLVM/bin/clang++.exe" ^
-DCMAKE_CXX_FLAGS="--target=x86_64-w64-mingw32 -stdlib=libstdc++ -pthread" ^
-DCMAKE_CXX_FLAGS_DEBUG="-g0" ^
-DCMAKE_EXE_LINKER_FLAGS="-fuse-ld=lld -lwinpthread" ^
-DCMAKE_EXE_LINKER_FLAGS="-lwinpthread" ^
-G"MinGW Makefiles" ^
-DCMAKE_BUILD_TYPE=Debug ^
-DJSON_BuildTests=On
@@ -216,7 +214,7 @@ jobs:
# import-std support. Its opt-in token is CMake-version-specific, so pin
# CMake to the version whose token is set in tests/module_cpp20/CMakeLists.txt.
- name: Get pinned CMake and ninja
uses: lukka/get-cmake@a89e43e22a96abafcd7a62db652a65ecd33052c9 # v4.4.4
uses: lukka/get-cmake@fffaaafeea488556c2c12dad60690008bc1caacb # v4.4.2
with:
cmakeVersion: 4.3.4
# CMAKE_CXX_FLAGS replaces CMake's MSVC defaults (which include /EHsc), and
-4
View File
@@ -1,7 +1,6 @@
{
"_comment": "Used by the ci_infer CMake target (#5715 item 4b). fail-on-issue makes CI fail on Infer findings; disable-issue-type is a type-level baseline for the ~174 pre-existing findings (all PULSE_UNNECESSARY_COPY*/PULSE_RESOURCE_LEAK/PULSE_CONST_REFABLE, mostly in test code) triaged in run https://github.com/nlohmann/json/actions/runs/35829411620 on commit 1054b2097, so CI fails only on a NEW issue type. Remove an entry here once its findings have been fixed or explicitly accepted.",
"_comment_pulse": "Pulse stops exploring paths after pulse-max-disjuncts (default 20). With the default, basic_json::replace_value() (destroy + assert_invariant) exceeds the limit, Pulse loses the stored type, and reports false NULLPTR_DEREFERENCE findings for get_ptr() results in tests/src/unit-pointer_access.cpp.",
"_comment_view": "Infer's model of std::unique_ptr mixes up values that are returned by value and own one: basic_json_document (parse() results) and the `built` values of the build() helper in tests/src/unit-json_view_builder.cpp. It reports USE_AFTER_DELETE for one of them after the destructor of an unrelated object (e.g. ~built() on line 345 invalidating `shallow` on line 350 of that file, or two documents parsed in one lambda in tests/src/unit-json_view_dump.cpp). AddressSanitizer and Valgrind are clean on the same tests, so reports for the json_view test files are excluded; findings reported in the library headers are still reported.",
"pulse-max-disjuncts": 40,
"fail-on-issue": true,
"disable-issue-type": [
@@ -11,8 +10,5 @@
"PULSE_UNNECESSARY_COPY_OPTIONAL",
"PULSE_RESOURCE_LEAK",
"PULSE_CONST_REFABLE"
],
"report-block-list-path-regex": [
"tests/src/unit-json_view.*\\.cpp"
]
}
-2
View File
@@ -37,7 +37,6 @@ cc_library(
"include/nlohmann/detail/input/parser.hpp",
"include/nlohmann/detail/input/position_t.hpp",
"include/nlohmann/detail/input/pow5_table.hpp",
"include/nlohmann/detail/input/simd_scan.hpp",
"include/nlohmann/detail/input/string_scan.hpp",
"include/nlohmann/detail/iterators/internal_iterator.hpp",
"include/nlohmann/detail/iterators/iter_impl.hpp",
@@ -90,7 +89,6 @@ cc_library(
"include/nlohmann/detail/view/simd.hpp",
"include/nlohmann/detail/view/string_ref.hpp",
"include/nlohmann/detail/view/value.hpp",
"include/nlohmann/detail/view/view_mode.hpp",
"include/nlohmann/json.hpp",
"include/nlohmann/json_fwd.hpp",
"include/nlohmann/json_literals.hpp",
-27
View File
@@ -6,7 +6,6 @@ This file describes the source for supporting files; that is, files that are not
- [GitHub](#github)
- [REUSE](#reuse)
- [Package Managers](#package-managers)
- [Debugging](#debugging)
## Continuous Integration
@@ -290,29 +289,3 @@ The module definition for [Bazel](https://bazel.build)'s [Bzlmod](https://bazel.
Further documentation:
- [Bazel modules](https://bazel.build/external/module)
## Debugging
### `nlohmann_json.natvis`
The [Natvis](https://learn.microsoft.com/en-us/visualstudio/debugger/create-custom-views-of-native-objects) file that
gives `json` values a friendly view in the Visual Studio debugger. The file is generated by
`tools/generate_natvis/generate_natvis.py` from the template `tools/generate_natvis/nlohmann_json.natvis.j2` and the ABI
tags and version in `include/nlohmann/detail/abi_macros.hpp`; change the script or the template rather than editing
the file by hand. The file can be updated by calling
```shell
make natvis
```
The "Check amalgamation" workflow fails if the file is out of date.
The file covers the namespace variants with up to two ABI tags. A Natvis file for other configurations can be
generated with the `--abi-tags` or `--all` options, for example
`make natvis NATVIS_ARGS="--abi-tags _diag,_dp,_ns --output my_nlohmann_json.natvis"`; see
[`tools/generate_natvis`](tools/generate_natvis/README.md). With MSVC, CMake adds the file to the `nlohmann_json`
target and installs it.
Further documentation:
- [Create custom views of C++ objects in the debugger using the Natvis framework](https://learn.microsoft.com/en-us/visualstudio/debugger/create-custom-views-of-native-objects)
+2 -4
View File
@@ -46,7 +46,7 @@ all:
@echo "clean - remove built files"
@echo "(fuzzers) - see tests/fuzzing.md, or run 'make -C tests fuzzers' to build the AFL fuzzers"
@echo "macro_builder_check - check that macro_scope.hpp matches tools/macro_builder's output"
@echo "natvis - regenerate nlohmann_json.natvis from the current ABI tags and version (pass generator options via NATVIS_ARGS, see tools/generate_natvis/README.md)"
@echo "natvis - regenerate nlohmann_json.natvis from the current ABI tags and version"
@echo "pretty - beautify code with Artistic Style"
@echo "pvs_studio - run the PVS-Studio static analyzer and open the report"
@echo "release - create the release files (include.zip, json.tar.xz, single headers, signatures, hashes)"
@@ -120,15 +120,13 @@ $(AMALGAMATED_VIEW_FILE): $(SRCS)
tools/amalgamate/amalgamate.py -c tools/amalgamate/config_json_view.json -s . --verbose=yes
NATVIS_VENV=tools/generate_natvis/venv
# extra options for generate_natvis.py, e.g. NATVIS_ARGS="--abi-tags _diag,_dp,_ns --output my.natvis"
NATVIS_ARGS=
# regenerate nlohmann_json.natvis from the ABI tags and version in include/nlohmann/detail/abi_macros.hpp
# (the dependencies are installed into a virtual environment first)
natvis:
@test -d $(NATVIS_VENV) || python3 -mvenv $(NATVIS_VENV)
@$(NATVIS_VENV)/bin/python3 -c 'import jinja2' 2>/dev/null || $(NATVIS_VENV)/bin/pip3 install --quiet -r tools/generate_natvis/requirements.txt
$(NATVIS_VENV)/bin/python3 tools/generate_natvis/generate_natvis.py $(NATVIS_ARGS) .
$(NATVIS_VENV)/bin/python3 tools/generate_natvis/generate_natvis.py .
# regenerate the two tools/macro_builder blocks of $(MACRO_SCOPE_HPP) (see its README.md) and diff against the
# checked-in header; phony, because it never writes $(MACRO_SCOPE_HPP) itself
+17 -29
View File
@@ -116,7 +116,7 @@ There is also a [**docset**](https://github.com/Kapeli/Dash-User-Contributions/t
- **Constructors**: [basic_json](https://json.nlohmann.me/api/basic_json/basic_json), [array](https://json.nlohmann.me/api/basic_json/array), [binary](https://json.nlohmann.me/api/basic_json/binary), [object](https://json.nlohmann.me/api/basic_json/object)
- **Object inspection**: [type](https://json.nlohmann.me/api/basic_json/type), [operator value_t](https://json.nlohmann.me/api/basic_json/operator_value_t), [type_name](https://json.nlohmann.me/api/basic_json/type_name), [is_primitive](https://json.nlohmann.me/api/basic_json/is_primitive), [is_structured](https://json.nlohmann.me/api/basic_json/is_structured), [is_null](https://json.nlohmann.me/api/basic_json/is_null), [is_boolean](https://json.nlohmann.me/api/basic_json/is_boolean), [is_number](https://json.nlohmann.me/api/basic_json/is_number), [is_number_integer](https://json.nlohmann.me/api/basic_json/is_number_integer), [is_number_unsigned](https://json.nlohmann.me/api/basic_json/is_number_unsigned), [is_number_float](https://json.nlohmann.me/api/basic_json/is_number_float), [is_object](https://json.nlohmann.me/api/basic_json/is_object), [is_array](https://json.nlohmann.me/api/basic_json/is_array), [is_string](https://json.nlohmann.me/api/basic_json/is_string), [is_binary](https://json.nlohmann.me/api/basic_json/is_binary), [is_discarded](https://json.nlohmann.me/api/basic_json/is_discarded)
- **Value access**: [get](https://json.nlohmann.me/api/basic_json/get), [get_to](https://json.nlohmann.me/api/basic_json/get_to), [get_ptr](https://json.nlohmann.me/api/basic_json/get_ptr), [get_ref](https://json.nlohmann.me/api/basic_json/get_ref), [operator ValueType](https://json.nlohmann.me/api/basic_json/operator_ValueType), [get_binary](https://json.nlohmann.me/api/basic_json/get_binary)
- **Element access**: [at](https://json.nlohmann.me/api/basic_json/at), [operator[]](https://json.nlohmann.me/api/basic_json/operator%5B%5D/), [value](https://json.nlohmann.me/api/basic_json/value), [front](https://json.nlohmann.me/api/basic_json/front), [back](https://json.nlohmann.me/api/basic_json/back)
- **Element access**: [at](https://json.nlohmann.me/api/basic_json/at), [operator[]](https://json.nlohmann.me/api/basic_json/operator[]), [value](https://json.nlohmann.me/api/basic_json/value), [front](https://json.nlohmann.me/api/basic_json/front), [back](https://json.nlohmann.me/api/basic_json/back)
- **Lookup**: [find](https://json.nlohmann.me/api/basic_json/find), [count](https://json.nlohmann.me/api/basic_json/count), [contains](https://json.nlohmann.me/api/basic_json/contains)
- **Iterators**: [begin](https://json.nlohmann.me/api/basic_json/begin), [cbegin](https://json.nlohmann.me/api/basic_json/cbegin), [end](https://json.nlohmann.me/api/basic_json/end), [cend](https://json.nlohmann.me/api/basic_json/cend), [rbegin](https://json.nlohmann.me/api/basic_json/rbegin), [rend](https://json.nlohmann.me/api/basic_json/rend), [crbegin](https://json.nlohmann.me/api/basic_json/crbegin), [crend](https://json.nlohmann.me/api/basic_json/crend), [items](https://json.nlohmann.me/api/basic_json/items)
- **Capacity**: [empty](https://json.nlohmann.me/api/basic_json/empty), [size](https://json.nlohmann.me/api/basic_json/size), [max_size](https://json.nlohmann.me/api/basic_json/max_size)
@@ -125,7 +125,7 @@ There is also a [**docset**](https://github.com/Kapeli/Dash-User-Contributions/t
- **Serialization / Dumping**: [dump](https://json.nlohmann.me/api/basic_json/dump)
- **Deserialization / Parsing**: [parse](https://json.nlohmann.me/api/basic_json/parse), [accept](https://json.nlohmann.me/api/basic_json/accept), [sax_parse](https://json.nlohmann.me/api/basic_json/sax_parse)
- **JSON Pointer functions**: [flatten](https://json.nlohmann.me/api/basic_json/flatten), [unflatten](https://json.nlohmann.me/api/basic_json/unflatten)
- **JSON Patch functions**: [patch](https://json.nlohmann.me/api/basic_json/patch), [patch_inplace](https://json.nlohmann.me/api/basic_json/patch_inplace), [diff](https://json.nlohmann.me/api/basic_json/diff), [merge_patch](https://json.nlohmann.me/api/basic_json/merge_patch), [merge_diff](https://json.nlohmann.me/api/basic_json/merge_diff)
- **JSON Patch functions**: [patch](https://json.nlohmann.me/api/basic_json/patch), [patch_inplace](https://json.nlohmann.me/api/basic_json/patch_inplace), [diff](https://json.nlohmann.me/api/basic_json/diff), [merge_patch](https://json.nlohmann.me/api/basic_json/merge_patch)
- **Static functions**: [meta](https://json.nlohmann.me/api/basic_json/meta), [get_allocator](https://json.nlohmann.me/api/basic_json/get_allocator)
- **Binary formats**: [from_bjdata](https://json.nlohmann.me/api/basic_json/from_bjdata), [from_bon8](https://json.nlohmann.me/api/basic_json/from_bon8), [from_bson](https://json.nlohmann.me/api/basic_json/from_bson), [from_cbor](https://json.nlohmann.me/api/basic_json/from_cbor), [from_msgpack](https://json.nlohmann.me/api/basic_json/from_msgpack), [from_ubjson](https://json.nlohmann.me/api/basic_json/from_ubjson), [to_bjdata](https://json.nlohmann.me/api/basic_json/to_bjdata), [to_bon8](https://json.nlohmann.me/api/basic_json/to_bon8), [to_bson](https://json.nlohmann.me/api/basic_json/to_bson), [to_cbor](https://json.nlohmann.me/api/basic_json/to_cbor), [to_msgpack](https://json.nlohmann.me/api/basic_json/to_msgpack), [to_ubjson](https://json.nlohmann.me/api/basic_json/to_ubjson)
- **Non-member functions**: [operator<<](https://json.nlohmann.me/api/operator_ltlt/), [operator>>](https://json.nlohmann.me/api/operator_gtgt/), [to_string](https://json.nlohmann.me/api/basic_json/to_string)
@@ -151,7 +151,7 @@ The `json` class provides an API for manipulating a JSON value. To create a `jso
```cpp
#include <fstream>
#include <nlohmann/json.hpp>
using nlohmann::json;
using json = nlohmann::json;
// ...
@@ -164,7 +164,7 @@ If using modules (enabled with `NLOHMANN_JSON_BUILD_MODULES`), this example beco
import std;
import nlohmann.json;
using nlohmann::json;
using json = nlohmann::json;
// ...
@@ -360,7 +360,7 @@ std::cout << cpp_string << " == " << cpp_string2 << " == " << j_string.get<std::
std::cout << j_string << " == " << serialized_string << std::endl;
```
[`.dump()`](https://json.nlohmann.me/api/basic_json/dump/) returns the serialized JSON text, so a string value is enclosed in quotes and special characters are escaped. Use [`get<std::string>()`](https://json.nlohmann.me/api/basic_json/get/) to retrieve the originally stored string value.
[`.dump()`](https://json.nlohmann.me/api/basic_json/dump/) returns the originally stored string value.
Note the library only supports UTF-8. When you store strings with different encodings in the library, calling [`dump()`](https://json.nlohmann.me/api/basic_json/dump/) may throw an exception unless `json::error_handler_t::replace`, `json::error_handler_t::ignore`, or `json::error_handler_t::keep` are used as error handlers.
@@ -687,15 +687,15 @@ json j_result = j_original.patch(j_patch);
// calculate a JSON patch from two JSON values
json::diff(j_result, j_original);
// [
// { "op": "replace", "path": "/baz", "value": ["one", "two", "three"] },
// { "op": "remove", "path": "/hello" },
// { "op":" replace", "path": "/baz", "value": ["one", "two", "three"] },
// { "op": "remove","path": "/hello" },
// { "op": "add", "path": "/foo", "value": "bar" }
// ]
```
### JSON Merge Patch
The library supports **JSON Merge Patch** ([RFC 7396](https://tools.ietf.org/html/rfc7396)) as a patch format. Instead of using JSON Pointer (see above) to specify values to be manipulated, it describes the changes using a syntax that closely mimics the document being modified.
The library supports **JSON Merge Patch** ([RFC 7386](https://tools.ietf.org/html/rfc7386)) as a patch format. Instead of using JSON Pointer (see above) to specify values to be manipulated, it describes the changes using a syntax that closely mimics the document being modified.
```cpp
// a JSON value
@@ -725,20 +725,6 @@ j_document.merge_patch(j_patch);
// }
```
Conversely, [`merge_diff`](https://json.nlohmann.me/api/basic_json/merge_diff/) creates a merge patch from two JSON values:
```cpp
// create a merge patch that turns j_original into j_document
json j_original = R"({"a": "b", "c": {"d": "e", "f": "g"}})"_json;
json::merge_diff(j_original, j_document);
// {
// "a": "z",
// "c": {
// "f": null
// }
// }
```
### Implicit conversions
Supported types can be implicitly converted to JSON values.
@@ -842,7 +828,7 @@ assert(p == p2);
To make this work with one of your types, you only need to provide two functions:
```cpp
using nlohmann::json;
using json = nlohmann::json;
namespace ns {
void to_json(json& j, const person& p) {
@@ -1257,7 +1243,7 @@ See the page [quality assurance](https://json.nlohmann.me/community/quality_assu
#include <nlohmann/json.hpp>
// for convenience
using nlohmann::json;
using json = nlohmann::json;
```
to the files you want to process JSON and set the necessary switches to enable C++11 (e.g., `-std=c++11` for GCC and Clang).
@@ -1288,9 +1274,13 @@ The package configuration file, `nlohmann_jsonConfig.cmake`, can be used either
To embed the library directly into an existing CMake project, place the entire source tree in a subdirectory and call `add_subdirectory()` in your `CMakeLists.txt` file:
```cmake
# Typically you don't care so much for a third party library's tests to be
# run from your own project's code.
set(JSON_BuildTests OFF CACHE INTERNAL "")
# If you only include this third party in PRIVATE source files, you do not
# need to install it when your main project gets installed.
set(JSON_Install OFF CACHE INTERNAL "")
# set(JSON_Install OFF CACHE INTERNAL "")
# Don't use include(nlohmann_json/CMakeLists.txt) since that carries with it
# unintended consequences that will break the build. It's generally
@@ -1305,8 +1295,8 @@ target_link_libraries(foo PRIVATE nlohmann_json::nlohmann_json)
##### Embedded (FetchContent)
Since CMake v3.14,
[FetchContent](https://cmake.org/cmake/help/v3.14/module/FetchContent.html) can
Since CMake v3.11,
[FetchContent](https://cmake.org/cmake/help/v3.11/module/FetchContent.html) can
be used to automatically download a release as a dependency at configure time.
Example:
@@ -1371,9 +1361,7 @@ Use your favorite [**package manager**](https://json.nlohmann.me/integration/pac
- <img src="https://raw.githubusercontent.com/nlohmann/json/refs/heads/develop/docs/mkdocs/docs/images/package_managers/swift.svg" height="20">&nbsp;[**Swift Package Manager**](https://json.nlohmann.me/integration/package_managers/#swift-package-manager) `nlohmann/json`
- <img src="https://raw.githubusercontent.com/nlohmann/json/refs/heads/develop/docs/mkdocs/docs/images/package_managers/nuget.svg" height="20">&nbsp;[**Nuget**](https://json.nlohmann.me/integration/package_managers/#nuget) `nlohmann.json`
- <img src="https://raw.githubusercontent.com/nlohmann/json/refs/heads/develop/docs/mkdocs/docs/images/package_managers/conda.svg" height="20">&nbsp;[**Conda**](https://json.nlohmann.me/integration/package_managers/#conda) `nlohmann_json`
- [**MSYS2**](https://json.nlohmann.me/integration/package_managers/#msys2) `mingw-w64-nlohmann-json`
- <img src="https://raw.githubusercontent.com/nlohmann/json/refs/heads/develop/docs/mkdocs/docs/images/package_managers/macports.svg" height="20">&nbsp;[**MacPorts**](https://json.nlohmann.me/integration/package_managers/#macports) `nlohmann-json`
- [**build2**](https://json.nlohmann.me/integration/package_managers/#build2) `nlohmann-json`
- <img src="https://raw.githubusercontent.com/nlohmann/json/refs/heads/develop/docs/mkdocs/docs/images/package_managers/CPM.png" height="20">&nbsp;[**cpm.cmake**](https://json.nlohmann.me/integration/package_managers/#cpmcmake) `gh:nlohmann/json`
- <img src="https://raw.githubusercontent.com/nlohmann/json/refs/heads/develop/docs/mkdocs/docs/images/package_managers/xmake.svg" height="20">&nbsp;[**xmake**](https://json.nlohmann.me/integration/package_managers/#xmake) `nlohmann_json`
+11 -30
View File
@@ -361,10 +361,10 @@ add_custom_target(ci_test_coverage
COMMAND ${CMAKE_COMMAND} --build ${PROJECT_BINARY_DIR}/build_coverage32
COMMAND cd ${PROJECT_BINARY_DIR}/build_coverage32 && ${CMAKE_CTEST_COMMAND} --parallel ${N} --output-on-failure
COMMAND ${LCOV_TOOL} --directory . --capture --output-file json.info --rc branch_coverage=1 --rc geninfo_unexecuted_blocks=1 --ignore-errors mismatch --ignore-errors unused --ignore-errors inconsistent
COMMAND ${LCOV_TOOL} -e json.info ${SRC_FILES} --output-file json.info.filtered --rc branch_coverage=1 --ignore-errors unused --ignore-errors inconsistent
COMMAND ${LCOV_TOOL} --directory . --capture --output-file json.info --rc branch_coverage=1 --rc geninfo_unexecuted_blocks=1 --ignore-errors mismatch --ignore-errors unused
COMMAND ${LCOV_TOOL} -e json.info ${SRC_FILES} --output-file json.info.filtered --rc branch_coverage=1 --ignore-errors unused
COMMAND ${CMAKE_SOURCE_DIR}/tests/thirdparty/imapdl/filterbr.py json.info.filtered > json.info.filtered.noexcept
COMMAND ${GENHTML_TOOL} --title "JSON for Modern C++" --legend --demangle-cpp --output-directory html --show-details --branch-coverage --ignore-errors inconsistent json.info.filtered.noexcept
COMMAND ${GENHTML_TOOL} --title "JSON for Modern C++" --legend --demangle-cpp --output-directory html --show-details --branch-coverage json.info.filtered.noexcept
COMMENT "Compile and test with coverage"
)
@@ -488,13 +488,6 @@ add_custom_target(ci_clang_analyze
# Check code with Cppcheck.
###############################################################################
# default_defines.hpp expands the Hedley macros to the compiler's feature-test operators, which Cppcheck does not know.
# Since Cppcheck 2.20, it rejects their invocations in #if conditions instead of evaluating them as 0.
file(WRITE ${CMAKE_BINARY_DIR}/cppcheck_feature_tests.hpp "")
foreach(OPERATOR __has_attribute __has_builtin __has_cpp_attribute __has_declspec_attribute __has_extension __has_feature __has_include __has_warning)
file(APPEND ${CMAKE_BINARY_DIR}/cppcheck_feature_tests.hpp "#define ${OPERATOR}(x) 0\n")
endforeach()
add_custom_target(ci_cppcheck
COMMAND mkdir -p cppcheck
COMMAND clang -dM -E -x c++ -std=c++11 ${CMAKE_SOURCE_DIR}/include/nlohmann/thirdparty/hedley/hedley.hpp > default_defines.hpp 2> /dev/null
@@ -503,7 +496,7 @@ add_custom_target(ci_cppcheck
COMMAND venv_cppcheck/bin/cppcheck --enable=warning --check-level=exhaustive --inline-suppr --inconclusive --force
--std=c++11 ${PROJECT_SOURCE_DIR}/include/nlohmann/json.hpp -I ${CMAKE_SOURCE_DIR}/include
--error-exitcode=1 --relative-paths=${PROJECT_SOURCE_DIR} -j ${N} --include=default_defines.hpp
--include=${CMAKE_BINARY_DIR}/cppcheck_feature_tests.hpp --cppcheck-build-dir=cppcheck
--cppcheck-build-dir=cppcheck
-UJSON_CATCH_USER -UJSON_TRY_USER -UJSON_ASSERT -UJSON_INTERNAL_CATCH -UJSON_THROW
-DJSON_HAS_CPP_11 -UJSON_HAS_CPP_14 -UJSON_HAS_CPP_17 -UJSON_HAS_CPP_20 -UJSON_HAS_THREE_WAY_COMPARISON
COMMENT "Check code with Cppcheck"
@@ -620,8 +613,9 @@ foreach(SRC_FILE ${SRC_FILES})
add_executable(single_${RELATIVE_SRC_FILE} EXCLUDE_FROM_ALL ${PROJECT_BINARY_DIR}/src_single/${RELATIVE_SRC_FILE}.cpp)
target_include_directories(single_${RELATIVE_SRC_FILE} PRIVATE ${PROJECT_SOURCE_DIR}/include)
target_compile_features(single_${RELATIVE_SRC_FILE} PRIVATE cxx_std_11)
if(RELATIVE_SRC_FILE STREQUAL "json")
# see below: report the diagnostics of json.hpp without --error, so they do not fail the build
if(RELATIVE_SRC_FILE STREQUAL "json" OR RELATIVE_SRC_FILE STREQUAL "json_literals")
# see below: report the diagnostics of json.hpp and json_literals.hpp without --error, so they
# do not fail the build
set_property(TARGET single_${RELATIVE_SRC_FILE} PROPERTY CXX_INCLUDE_WHAT_YOU_USE ${IWYU_TOOL} -Xiwyu --max_line_length=300)
else()
set_property(TARGET single_${RELATIVE_SRC_FILE} PROPERTY CXX_INCLUDE_WHAT_YOU_USE "${iwyu_path_and_options}")
@@ -635,31 +629,18 @@ foreach(SRC_FILE ${SRC_FILES})
# reporting its diagnostics (informational, via CXX_INCLUDE_WHAT_YOU_USE above) but exclude it
# from the hard gate below so a fresh IWYU/compiler combination does not fail this target on a
# nondeterministic suggestion for a header that already re-exports everything on purpose.
if(NOT RELATIVE_SRC_FILE STREQUAL "json")
# json_literals.hpp and json.hpp include each other on purpose (json.hpp includes it at its end
# unless JSON_NO_AUTOMATIC_UDLS is defined), and IWYU, not following the cycle, suggests replacing
# json.hpp with json_fwd.hpp although the literals need the complete basic_json; exclude it, too.
if(NOT RELATIVE_SRC_FILE STREQUAL "json" AND NOT RELATIVE_SRC_FILE STREQUAL "json_literals")
list(APPEND single_binaries_tus src_single/${RELATIVE_SRC_FILE}.cpp)
endif()
endforeach()
# The checks above look at each header on its own. Client code that includes only <nlohmann/json.hpp>
# must not be told by include analyzers to include another nlohmann header for what it uses
# (issue #5812): json.hpp marks those includes "IWYU pragma: export", and both IWYU and clang-tidy's
# misc-include-cleaner (disabled in .clang-tidy for the library itself) check these clients.
file(GLOB CONSUMER_FILES ${PROJECT_SOURCE_DIR}/tests/iwyu_consumer/*.cpp)
foreach(CONSUMER_FILE ${CONSUMER_FILES})
get_filename_component(CONSUMER_NAME "${CONSUMER_FILE}" NAME_WE)
add_executable(iwyu_consumer_${CONSUMER_NAME} EXCLUDE_FROM_ALL ${CONSUMER_FILE})
target_include_directories(iwyu_consumer_${CONSUMER_NAME} PRIVATE ${PROJECT_SOURCE_DIR}/include)
target_compile_features(iwyu_consumer_${CONSUMER_NAME} PRIVATE cxx_std_11)
list(APPEND single_binaries iwyu_consumer_${CONSUMER_NAME})
list(APPEND single_binaries_tus ${CONSUMER_FILE})
endforeach()
if(IWYU_TOOL_PY)
add_custom_target(ci_single_binaries
DEPENDS ${single_binaries}
COMMAND ${IWYU_TOOL_PY} -p ${PROJECT_BINARY_DIR} ${single_binaries_tus} -- ${iwyu_options}
COMMAND ${CLANG_TIDY_TOOL} -p ${PROJECT_BINARY_DIR} --checks=-*,misc-include-cleaner --warnings-as-errors=* ${CONSUMER_FILES}
VERBATIM
COMMENT "Check if headers are self-contained"
)
else()
+1 -1
View File
@@ -1 +1 @@
cppcheck==1.5.3
cppcheck==1.5.1
+1 -2
View File
@@ -341,14 +341,13 @@ def download(url, docs) -> str:
raise ValueError(f'not an http(s) URL: {url}')
req = urllib.request.Request(u.geturl(), headers={'User-Agent': USER_AGENT})
# (the scheme is checked above)
# nosemgrep: python.lang.security.audit.dynamic-urllib-use-detected.dynamic-urllib-use-detected
with urllib.request.urlopen(req, timeout=20) as r: # nosec B310
data = r.read()
ctype = r.headers.get_content_type()
path = urllib.parse.unquote(u.path).lstrip('/')
ext = os.path.splitext(path)[1]
if u.query or not ext or path.endswith('/'):
digest = hashlib.sha256(url.encode()).hexdigest()[:12]
digest = hashlib.sha1(url.encode(), usedforsecurity=False).hexdigest()[:12]
path = os.path.join(os.path.dirname(path), digest + CONTENT_TYPE_EXT.get(ctype, ext or '.bin'))
rel = os.path.normpath(os.path.join('assets', 'external', u.hostname, path))
out = os.path.join(docs, rel)
@@ -30,7 +30,7 @@ class (either explicitly or via the conversion operators).
## Return value
1. (none) — the converted value is written to the output parameter `val`.
1. (none) -- the converted value is written to the output parameter `val`.
2. the JSON value `j` converted to `TargetType`
## Examples
@@ -67,9 +67,7 @@ class (either explicitly or via the conversion operators).
## See also
- [`to_json`](to_json.md) - convert a C++ value to JSON
- [Arbitrary Type Conversions](../../features/arbitrary_types.md) - write your own `from_json` and `to_json` functions
- [Converting values](../../features/conversions.md) - overview of `get`, `get_to` and implicit conversions
- [to_json](to_json.md)
## Version history
@@ -30,14 +30,6 @@ struct adl_serializer {
- [**from_json**](from_json.md) - convert a JSON value to any value type
- [**to_json**](to_json.md) - convert any value type to a JSON value
## See also
- [Arbitrary type conversions](../../features/arbitrary_types.md) - how to make your types convertible
- [`get`](../basic_json/get.md) - / [`get_to`](../basic_json/get_to.md) - convert a JSON value to a C++ type
- [`basic_json`](../basic_json/basic_json.md) - construct a JSON value from a C++ value
- [`NLOHMANN_DEFINE_TYPE_INTRUSIVE`](../macros/nlohmann_define_type_intrusive.md) - generate the conversion functions for a type
- [Specializing enum conversion](../../features/enum_conversion.md) - serializing enums as JSON strings
## Version history
- Added in version 2.1.0.
@@ -36,9 +36,7 @@ This function is usually called by the constructors of the [basic_json](../basic
## See also
- [`from_json`](from_json.md) - convert JSON to a C++ value
- [Arbitrary Type Conversions](../../features/arbitrary_types.md) - write your own `from_json` and `to_json` functions
- [Converting values](../../features/conversions.md) - overview of `get`, `get_to` and implicit conversions
- [from_json](from_json.md)
## Version history
+4 -41
View File
@@ -23,9 +23,6 @@ Checks whether the input is valid JSON.
respectively as UTF-8, UTF-16, and UTF-32. If `SentinelType` differs from `IteratorType`, it must be comparable to
the iterator type with `operator!=`.
Ill-formed UTF-16 and UTF-32 sequences are rejected: a lone surrogate, a high surrogate that is not followed by its
low surrogate, and a code point above `U+10FFFF` all make this function return `false`.
Unlike the [`parse()`](parse.md) function, this function neither throws an exception in case of invalid JSON input
(i.e., a parse error) nor creates diagnostic information.
@@ -38,12 +35,9 @@ Unlike the [`parse()`](parse.md) function, this function neither throws an excep
- a `#!c FILE` pointer (throws if null)
- a C-style array of characters
- a pointer to a null-terminated string of single byte characters (throws if null)
- a `std::string` or a `std::string_view` (C++17)
- a `std::string`
- a container `obj` for which `begin(obj)` and `end(obj)` produce a valid pair of iterators
(as found via ADL or member functions, with semantics compatible to `std::begin` and `std::end`)
- wide characters (`wchar_t`, `char16_t`, `char32_t`), which are converted to UTF-8: a wide string object
(`std::wstring`, `std::u16string`, `std::u32string`) or an array (e.g. a wide string literal); a pointer to a
null-terminated wide string (e.g. `std::u16string::c_str()`) is not supported
`IteratorType`
: a compatible iterator type, for instance.
@@ -131,37 +125,13 @@ outside of a string, invalid) byte; see the [FAQ entry](../../home/faq.md#nul-by
--8<-- "examples/accept__iterator_pair.output"
```
??? example "Example: (3) reading from UTF-16 strings"
The encoding is deduced from the character type of the input. String literals like `u"..."`, `U"..."`, and
`L"..."` work as well.
```cpp
--8<-- "examples/accept__wide_string.cpp"
```
Output:
```json
--8<-- "examples/accept__wide_string.output"
```
## See also
- [`parse`](parse.md) - deserialize from a compatible input
- [`sax_parse`](sax_parse.md) - parse input using the SAX interface
- [`operator>>`](../operator_gtgt.md) - deserialize from stream
- [parse](parse.md) - deserialize from a compatible input
- [sax_parse](sax_parse.md) - parse input using the SAX interface
- [operator>>](../operator_gtgt.md) - deserialize from stream
- [`JSON_STRICT_NUL_HANDLING`](../macros/json_strict_nul_handling.md) - opt in to rejecting a NUL byte in the input
instead of treating it as end of input
- [`JSON_DISABLE_STREAM_BULK_SCAN`](../macros/json_disable_stream_bulk_scan.md) - read a `std::istream` one character
at a time
- [`JSON_DISABLE_UNLOCKED_FILE_IO`](../macros/json_disable_unlocked_file_io.md) - read a `FILE*` with the locking stdio
functions
- [Parsing](../../features/parsing/index.md) - overview of the parsing functions
- [Comments](../../features/comments.md) - ignore `//` and `/* */` comments while parsing
- [Trailing Commas](../../features/trailing_commas.md) - accept trailing commas in arrays and objects
- [Parsing and Exceptions](../../features/parsing/parse_exceptions.md) - handling parse errors and locating them in the input
- [Parsing Untrusted Input](../../features/parsing/untrusted_input.md) - limits and checks for input you do not control
## Version history
@@ -173,13 +143,6 @@ outside of a string, invalid) byte; see the [FAQ entry](../../home/faq.md#nul-by
- Extended overload (2) to accept heterogeneous iterator+sentinel pairs (C++20 ranges support) in version 3.13.0.
- `JSON_STRICT_NUL_HANDLING` added in version 3.13.0 to optionally reject a NUL byte in the input instead of treating
it as end of input; planned to become the default in version 4.0.0.
- Parsing from an `std::istream` scans the characters in its stream buffer in bulk in version 3.13.0
([`JSON_DISABLE_STREAM_BULK_SCAN`](../macros/json_disable_stream_bulk_scan.md)).
- Parsing from a `FILE*` locks the file once instead of once per character in version 3.13.0
([`JSON_DISABLE_UNLOCKED_FILE_IO`](../macros/json_disable_unlocked_file_io.md)).
- Ill-formed UTF-16 and UTF-32 input (a lone surrogate, a high surrogate that is not followed by its low surrogate, or
a code point above `U+10FFFF`) is rejected in version 3.13.0; before that, some such sequences were accepted or
ended the input silently.
!!! warning "Deprecation"
+2 -2
View File
@@ -29,9 +29,9 @@ Linear in the size of `init`.
This function is only needed to express two edge cases that cannot be realized with the initializer list constructor
([`basic_json(initializer_list_t, bool, value_t)`](basic_json.md)). These cases are:
1. creating an array whose elements are all pairs whose first element is a string — in this case, the initializer list
1. creating an array whose elements are all pairs whose first element is a string -- in this case, the initializer list
constructor would create an object, taking the first elements as keys
2. creating an empty array — passing the empty initializer list to the initializer list constructor yields an empty
2. creating an empty array -- passing the empty initializer list to the initializer list constructor yields an empty
object
## Examples
+5 -7
View File
@@ -27,7 +27,7 @@ To store objects in C++, a type is defined by the template parameters explained
### Default type
With the default values for `ArrayType` (`std::vector`) and `AllocatorType` (`std::allocator`), the default type for
With the default values for `ArrayType` (`std::vector`) and `AllocatorType` (`std::allocator`), the default value for
`array_t` is:
```cpp
@@ -69,12 +69,10 @@ Arrays are stored as pointers in a `basic_json` type. That is, for any access to
## See also
- [`object_t`](object_t.md) - the type used to store JSON objects
- [`binary_t`](binary_t.md) - the type used to store binary values
- [`is_array`](is_array.md) - checks whether the JSON value is an array
- [`max_size`](max_size.md) - returns the maximum possible number of elements
- [Types](../../features/types/index.md) - how arrays are stored
- [Template Parameter Requirements](../../features/types/template_parameters.md) - requirements on the `ArrayType` template parameter
- [object_t](object_t.md) the type used to store JSON objects
- [binary_t](binary_t.md) the type used to store binary values
- [is_array](is_array.md) checks whether the JSON value is an array
- [max_size](max_size.md) returns the maximum possible number of elements
## Version history
@@ -46,8 +46,7 @@ The function is equivalent to `static_cast<json_base_class_t&>(j)` (or `static_c
## See also
- [`json_base_class_t`](json_base_class_t.md) - type of the custom base class
- [Template Parameter Requirements](../../features/types/template_parameters.md) - requirements on the `CustomBaseClass` template parameter
- [json_base_class_t](json_base_class_t.md) - type of the custom base class
## Version history
+8 -10
View File
@@ -90,8 +90,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
1. Constant.
2. Logarithmic in the size of the container.
3. Logarithmic in the size of the container.
4. Linear in the number of reference tokens of `ptr`; for each of them, logarithmic in the size of the object, or
constant for an array.
4. Logarithmic in the size of the container.
## Notes
@@ -231,19 +230,18 @@ Strong exception safety: if an exception occurs, the original value stays intact
## See also
- [Checked access](../../features/element_access/checked_access.md) - element access with range checking
- [`operator[]`](operator%5B%5D.md) - unchecked access by reference
- [`value`](value.md) - access with default value
- [`basic_json_view::at`](../basic_json_view/at.md) - the same access on a zero-copy view
- [Element Access](../../features/element_access/index.md) - overview of all ways to access elements
- [JSON Pointer](../../features/json_pointer.md) - access nested values with a pointer
- documentation on [checked access](../../features/element_access/checked_access.md)
- [`operator[]`](operator%5B%5D.md) for unchecked access by reference
- [`value`](value.md) for access with default value
- [basic_json_view::at](../basic_json_view/at.md) - the same access on a zero-copy view
## Version history
1. Added in version 1.0.0.
2. Added in version 1.0.0.
3. Added in version 3.11.0. Support for keys convertible to `std::string_view` added in version 3.13.0, consistently
across the lookup functions.
3. Added in version 3.11.0. Fixed in version 3.13.0 to consistently accept `std::string_view`-convertible keys, as
already supported by [`operator[]`](operator[].md), [`value`](value.md), [`find`](find.md), and other lookup
functions.
4. Added in version 2.0.0. Throws [`parse_error.109`](../../home/exceptions.md#jsonexceptionparse_error109) instead of
[`out_of_range.404`](../../home/exceptions.md#jsonexceptionout_of_range404) for a one-character array index that is not
a digit (e.g., `/x`) in version 3.13.0, as it already did for longer ones.
+3 -4
View File
@@ -57,11 +57,10 @@ Constant.
## See also
- [`front`](front.md) - to access the first element
- [`basic_json_view::back`](../basic_json_view/back.md) - the same access on a zero-copy view
- [Element Access](../../features/element_access/index.md) - overview of all ways to access elements
- [front](front.md) to access the first element
- [basic_json_view::back](../basic_json_view/back.md) - the same access on a zero-copy view
## Version history
- Added in version 1.0.0.
- Binary values are supported since version 3.8.0.
- Adjusted code to return reference to binary values in version 3.8.0.
+20 -34
View File
@@ -52,7 +52,7 @@ basic_json(basic_json&& other) noexcept;
The postcondition of this constructor can be restored by calling [`clear()`](clear.md).
2. Create a `#!json null` JSON value. It either takes a null pointer as parameter (explicitly creating `#!json null`)
or no parameter (implicitly creating `#!json null`). The passed null pointer itself is not read — it is only used to
or no parameter (implicitly creating `#!json null`). The passed null pointer itself is not read -- it is only used to
choose the right constructor.
3. This is a "catch all" constructor for all compatible JSON types; that is, types for which a `to_json()` method
@@ -68,14 +68,6 @@ basic_json(basic_json&& other) noexcept;
`std::unordered_map`, `std::multimap`, and `std::unordered_multimap` with a `key_type` compatible to `string_t`
and a `value_type` from which a `basic_json` value can be constructed.
- **strings**: `string_t`, string literals, and all compatible string containers can be used.
!!! note "Rvalue containers are moved from"
If `val` is an rvalue of a compatible array-like or object-like container other than `array_t`/`object_t`
(e.g., `json j = std::move(vec);` or `json j(std::vector<std::string>{...});`), the elements are moved into
the JSON value instead of copied. Afterwards, the elements of the source container are in a valid but
unspecified state (**moved-from**). Keys of associative containers are `const` and therefore still copied.
Lvalues and `const` rvalues are copied, and the source is left unchanged.
- **numbers**: [`number_integer_t`](number_integer_t.md), [`number_unsigned_t`](number_unsigned_t.md),
[`number_float_t`](number_float_t.md), and all convertible number types such as `int`, `size_t`, `int64_t`, `float`
or `double` can be used.
@@ -113,22 +105,19 @@ basic_json(basic_json&& other) noexcept;
```mermaid
flowchart TD
A(["initializer_list init"]) --> B{{"empty, or every element is a 2-element<br/>array whose first element is a string?"}}
B -->|"yes"| C{{"type_deduction"}}
B -->|"no"| D{{"type_deduction"}}
A(["initializer_list init"]) --> B{"empty, or every element is a 2-element<br/>array whose first element is a string?"}
B -->|"yes"| C{"type_deduction"}
B -->|"no"| D{"type_deduction"}
C -->|"true"| OBJ["create object"]
C -->|"false"| E{{"manual_type"}}
C -->|"false"| E{"manual_type"}
E -->|"object"| OBJ
E -->|"array"| ARR["create array"]
D -->|"true"| ARR
D -->|"false"| F{{"manual_type"}}
D -->|"false"| F{"manual_type"}
F -->|"array"| ARR
F -->|"object"| ERR["throw type_error.301"]
```
<p class="nj-caption" markdown>Decision flow for an initializer list: hexagons are checks, edge labels are their
outcomes, and rectangles are the resulting value or exception.</p>
The rules aim to create the best fit between a C++ initializer list and JSON values. The rationale is as follows:
1. The empty initializer list is written as `#!cpp {}` which is exactly an empty JSON object.
@@ -247,9 +236,7 @@ basic_json(basic_json&& other) noexcept;
2. No-throw guarantee: this constructor never throws exceptions.
3. Depends on the called constructor. For types directly supported by the library (i.e., all types for which no
`to_json()` function was provided), a strong guarantee holds: if an exception is thrown, there are no changes to any
JSON value. **Exception:** when `val` is an rvalue array-like or object-like container, its elements are moved one
by one; if an exception is thrown in the middle of the conversion (e.g., an allocation failure), the JSON value is
unchanged, but the source container may be left partially moved-from.
JSON value.
4. Depends on the called constructor. For types directly supported by the library (i.e., all types for which no
`to_json()` function was provided), a strong guarantee holds: if an exception is thrown, there are no changes to any
JSON value.
@@ -476,25 +463,24 @@ basic_json(basic_json&& other) noexcept;
## See also
- [`array`](array.md) - create a JSON array value, forcing array creation from an initializer list even when it looks like
- [array](array.md) create a JSON array value, forcing array creation from an initializer list even when it looks like
an object
- [`object`](object.md) - create a JSON object value, forcing object creation from an initializer list
- [`binary`](binary.md) - create a JSON binary array value
- [`operator=`](operator=.md) - copy assignment operator
- [object](object.md) create a JSON object value, forcing object creation from an initializer list
- [binary](binary.md) create a JSON binary array value
- [operator=](operator=.md) copy assignment operator
- [Creating JSON values](../../features/creating_values.md) - the article on creating JSON values
- [Converting values](../../features/conversions.md) - which C++ types can be converted
## Version history
1. Added in version 1.0.0.
2. Added in version 1.0.0.
3. Added in version 2.1.0.
4. Added in version 3.1.2. Explicit for different string types if `JSON_USE_IMPLICIT_CONVERSIONS` is `0` since
1. Since version 1.0.0.
2. Since version 1.0.0.
3. Since version 2.1.0.
4. Since version 3.2.0. Explicit for different string types if `JSON_USE_IMPLICIT_CONVERSIONS` is `0` since
version 3.13.0.
5. Added in version 1.0.0.
6. Added in version 1.0.0.
7. Added in version 1.0.0. Fixed in version 3.13.0 to also check the iterator range for binary values; before, a range
5. Since version 1.0.0.
6. Since version 1.0.0.
7. Since version 1.0.0. Fixed in version 3.13.0 to also check the iterator range for binary values; before, a range
that did not cover the whole value (such as `(end(), end())`) was accepted and the whole binary value was copied,
unlike the other primitive types.
8. Added in version 1.0.0.
9. Added in version 1.0.0.
8. Since version 1.0.0.
9. Since version 1.0.0.
+6 -11
View File
@@ -7,12 +7,7 @@ const_iterator begin() const noexcept;
Returns an iterator to the first element.
<div class="nj-fig-wrap" markdown>
--8<-- "images/range-begin-end.svg"
</div>
<p class="nj-caption" markdown>`begin()` points to the first element and `end()` to the position after the last element;
the dashed cell is the past-the-last position, which must not be dereferenced.</p>
![Illustration from cppreference.com](../../images/range-begin-end.svg)
## Return value
@@ -44,12 +39,12 @@ Constant.
## See also
- [`end`](end.md) - returns an iterator to one past the last element
- [`cbegin`](cbegin.md) - returns a const iterator to the first element
- [`rbegin`](rbegin.md) - returns a reverse iterator to the last element
- [`items`](items.md) - returns an iteration proxy to access keys and values during range-based for loops
- [end](end.md) returns an iterator to one past the last element
- [cbegin](cbegin.md) returns a const iterator to the first element
- [rbegin](rbegin.md) returns a reverse iterator to the last element
- [items](items.md) returns an iteration proxy to access keys and values during range-based for loops
- [Iterators](../../features/iterators.md) - the article on iterators
- [`basic_json_view::begin`](../basic_json_view/begin.md) - the same iteration on a zero-copy view (in document order,
- [basic_json_view::begin](../basic_json_view/begin.md) - the same iteration on a zero-copy view (in document order,
not sorted by key)
## Version history
+4 -5
View File
@@ -63,11 +63,10 @@ initialization of a binary array type, for backwards compatibility and so it doe
## See also
- [Binary formats](../../features/binary_formats/index.md) - formats that can store binary values
- [`binary_t`](binary_t.md) - type for binary values
- [`get_binary`](get_binary.md) - get a reference to the stored binary value
- [`is_binary`](is_binary.md) - return whether the value is binary
- [`byte_container_with_subtype`](../byte_container_with_subtype/index.md) - container for binary values with subtype
- [binary_t](binary_t.md) type for binary values
- [get_binary](get_binary.md) get a reference to the stored binary value
- [is_binary](is_binary.md) return whether the value is binary
- [byte_container_with_subtype](../byte_container_with_subtype/index.md) container for binary values with subtype
- [Binary Values](../../features/binary_values.md) - the article on binary values
## Version history
+4 -7
View File
@@ -41,7 +41,7 @@ represent a byte array in modern C++.
[`byte_container_with_subtype`](../byte_container_with_subtype/index.md) derives directly from it. Its
`value_type` must additionally be exactly one byte wide (e.g., `std::uint8_t`/`char`/`std::byte`): the binary
serializers (CBOR, MessagePack, BSON, UBJSON) read and write the container's raw bytes via
`reinterpret_cast`, which is only correct for byte-sized elements — a container like
`reinterpret_cast`, which is only correct for byte-sized elements -- a container like
`#!cpp std::vector<std::intptr_t>` will not work as `BinaryType`. The elements must be stored contiguously, and
the binary readers additionally require `resize()` and `operator[]`. See
[Template Parameter Requirements](../../features/types/template_parameters.md#binarytype) for the full list.
@@ -90,9 +90,8 @@ type `#!cpp binary_t*` must be dereferenced.
- MessagePack
- If a subtype is given and the binary array contains exactly 1, 2, 4, 8, or 16 elements, the fixext family (fixext1,
fixext2, fixext4, fixext8, fixext16) is used. For other sizes, the ext family (ext8, ext16, ext32) is used. The
subtype is then written as the signed 8-bit ext type: subtypes 128 to 255 map to the negative (reserved) ext
types, and on reading the ext type is exposed as an unsigned subtype from 0 to 255.
fixext2, fixext4, fixext8) is used. For other sizes, the ext family (ext8, ext16, ext32) is used. The subtype is
then added as a signed 8-bit integer.
- If no subtype is given, the bin family (bin8, bin16, bin32) is used.
- BSON
@@ -118,9 +117,7 @@ type `#!cpp binary_t*` must be dereferenced.
## See also
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [Binary formats](../../features/binary_formats/index.md) - formats that can store binary values
- [`byte_container_with_subtype`](../byte_container_with_subtype/index.md) - container type used by binary values
- [byte_container_with_subtype](../byte_container_with_subtype/index.md)
## Version history
@@ -1,48 +0,0 @@
# <small>nlohmann::basic_json::</small>bjdata_version_t
```cpp
enum class bjdata_version_t
{
draft2,
draft3
};
```
This enumeration is used in [`to_bjdata`](to_bjdata.md) to choose the version of the BJData specification to write:
draft2
: BJData Draft 2 (the default). Binary values are written as arrays of `U` integers, and ND-arrays with
`"_ArrayType_": "byte"` are written as regular objects, since the `B` marker is not part of Draft 2.
draft3
: BJData Draft 3. Binary values are written as `B` elements: as an optimized binary array (`[$B#`) if both `use_size`
and `use_type` are set, and as an array of `B`-prefixed elements otherwise. ND-arrays with
`"_ArrayType_": "byte"` are written as packed arrays (`[$B#[...]`).
Only the writer is affected by the version. [`from_bjdata`](from_bjdata.md) reads the markers of both drafts.
## Examples
??? example
The example below shows how the different values of the `bjdata_version_t` influence the serialization of a binary
value with [`to_bjdata`](to_bjdata.md).
```cpp
--8<-- "examples/bjdata_version_t.cpp"
```
Output:
```json
--8<-- "examples/bjdata_version_t.output"
```
## See also
- [to_bjdata](to_bjdata.md) serializes a JSON value to BJData
- [BJData](../../features/binary_formats/bjdata.md) - the article on the BJData format
## Version history
- Added in version 3.12.0.
+2 -4
View File
@@ -23,7 +23,7 @@ To store boolean values in C++, a type is defined by the template parameter `Bo
### Default type
With the default values for `BooleanType` (`#!cpp bool`), the default type for `boolean_t` is `#!cpp bool`.
With the default values for `BooleanType` (`#!cpp bool`), the default value for `boolean_t` is `#!cpp bool`.
### Storage
@@ -47,9 +47,7 @@ Boolean values are stored directly inside a `basic_json` type.
## See also
- [`is_boolean`](is_boolean.md) - checks whether the JSON value is a boolean
- [Types](../../features/types/index.md) - how booleans are stored
- [Template Parameter Requirements](../../features/types/template_parameters.md) - requirements on the `BooleanType` template parameter
- [is_boolean](is_boolean.md) checks whether the JSON value is a boolean
## Version history
+5 -10
View File
@@ -6,12 +6,7 @@ const_iterator cbegin() const noexcept;
Returns an iterator to the first element.
<div class="nj-fig-wrap" markdown>
--8<-- "images/range-begin-end.svg"
</div>
<p class="nj-caption" markdown>`cbegin()` points to the first element, like `begin()`, and `end()` to the position after
the last element; the dashed cell is the past-the-last position, which must not be dereferenced.</p>
![Illustration from cppreference.com](../../images/range-begin-end.svg)
## Return value
@@ -43,11 +38,11 @@ Constant.
## See also
- [`begin`](begin.md) - returns an iterator to the first element
- [`cend`](cend.md) - returns a const iterator to one past the last element
- [`crbegin`](crbegin.md) - returns a const reverse iterator to the last element
- [begin](begin.md) returns an iterator to the first element
- [cend](cend.md) returns a const iterator to one past the last element
- [crbegin](crbegin.md) returns a const reverse iterator to the last element
- [Iterators](../../features/iterators.md) - the article on iterators
- [`basic_json_view::cbegin`](../basic_json_view/cbegin.md) - the same iteration on a zero-copy view
- [basic_json_view::cbegin](../basic_json_view/cbegin.md) - the same iteration on a zero-copy view
## Version history
@@ -15,13 +15,11 @@ error
: report a parse error in case of a tag (the `from_cbor` overloads throw a `parse_error` exception by default)
ignore
: ignore tags (also in front of a text string map key)
: ignore tags
store
: store tagged byte strings (for bytes 0xd8..0xdb) as binary values with the tag as subtype; other tagged values are
read as if the tag were ignored. If several tags precede a byte string, only the tag directly in front of it is
stored, and only when it has the form 0xd8..0xdb (a tag 0..23 written as 0xc0..0xd7 is skipped). Tags in front of a
text string map key are skipped.
read as if the tag were ignored. If several tags precede a byte string, only the innermost one is stored.
## Examples
@@ -42,9 +40,8 @@ store
## See also
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [`from_cbor`](from_cbor.md) - deserializes a JSON value from CBOR
- [`input_format_t`](input_format_t.md) - the enumeration of supported input formats
- [from_cbor](from_cbor.md) deserializes a JSON value from CBOR
- [input_format_t](input_format_t.md) the enumeration of supported input formats
- [CBOR](../../features/binary_formats/cbor.md) - the article on the CBOR format
## Version history
+5 -10
View File
@@ -6,12 +6,7 @@ const_iterator cend() const noexcept;
Returns an iterator to one past the last element.
<div class="nj-fig-wrap" markdown>
--8<-- "images/range-begin-end.svg"
</div>
<p class="nj-caption" markdown>`cend()` points to the position after the last element, like `end()`, and `begin()` to
the first element; the dashed cell is the past-the-last position, which must not be dereferenced.</p>
![Illustration from cppreference.com](../../images/range-begin-end.svg)
## Return value
@@ -43,11 +38,11 @@ Constant.
## See also
- [`end`](end.md) - returns an iterator to one past the last element
- [`cbegin`](cbegin.md) - returns a const iterator to the first element
- [`crend`](crend.md) - returns a const reverse iterator to one before the first element
- [end](end.md) returns an iterator to one past the last element
- [cbegin](cbegin.md) returns a const iterator to the first element
- [crend](crend.md) returns a const reverse iterator to one before the first element
- [Iterators](../../features/iterators.md) - the article on iterators
- [`basic_json_view::cend`](../basic_json_view/cend.md) - the same iteration on a zero-copy view
- [basic_json_view::cend](../basic_json_view/cend.md) - the same iteration on a zero-copy view
## Version history
+2 -3
View File
@@ -54,9 +54,8 @@ All iterators, pointers, and references related to this container are invalidate
## See also
- [`erase`](erase.md) - removes elements from a JSON value
- [`empty`](empty.md) - checks whether the JSON value has no elements
- [Modifying values](../../features/modifying_values.md) - the article on modifying values
- [erase](erase.md) removes elements from a JSON value
- [empty](empty.md) checks whether the JSON value has no elements
## Version history
+8 -15
View File
@@ -61,18 +61,11 @@ Strong exception safety: if an exception occurs, the original value stays intact
## Complexity
1. Logarithmic in the size of the JSON object.
2. Logarithmic in the size of the JSON object.
3. At most one lookup per reference token of `ptr`, each logarithmic in the size of the container at that level:
O(*n* log *m*) for *n* reference tokens and containers of size at most *m*.
4. Deleted; a call with an integral argument does not compile.
Logarithmic in the size of the JSON object.
## Notes
- Overloads (1) and (2) always return `#!cpp false` when executed on a JSON type that is not an object. Overload (3)
also works on arrays and on primitive values: the empty JSON pointer resolves in every JSON value (so
`#!cpp json(1).contains(""_json_pointer)` returns `#!cpp true`), and `#!cpp json({1, 2}).contains("/1"_json_pointer)`
returns `#!cpp true`.
- This method always returns `#!cpp false` when executed on a JSON type that is not an object.
- This method can be executed on any JSON value type.
- Calling this function with an integer argument (for example, `#!cpp contains(0)`) does not compile: such an argument
would otherwise implicitly convert to a null `#!cpp const char*` and, from there, cause undefined behavior when
@@ -141,16 +134,16 @@ Strong exception safety: if an exception occurs, the original value stays intact
## See also
- [`find`](find.md) - find a value in an object
- [`count`](count.md) - returns the number of occurrences of a key
- [`basic_json_view::contains`](../basic_json_view/contains.md) - the same check on a zero-copy view
- [Element Access](../../features/element_access/index.md#does-this-key-exist) - how to test whether a key exists
- [find](find.md) find a value in an object
- [count](count.md) returns the number of occurrences of a key
- [basic_json_view::contains](../basic_json_view/contains.md) - the same check on a zero-copy view
## Version history
1. Added in version 3.11.0.
2. Added in version 3.6.0. Extended template `KeyType` to support comparable types in version 3.11.0. Support for keys
convertible to `std::string_view` added in version 3.13.0, consistently across the lookup functions.
2. Added in version 3.6.0. Extended template `KeyType` to support comparable types in version 3.11.0. Fixed in
version 3.13.0 to consistently accept `std::string_view`-convertible keys, as already supported by
[`operator[]`](operator[].md), [`at`](at.md), [`value`](value.md), and other lookup functions.
3. Added in version 3.7.0.
4. Deleted overloads for integral key types added in version 3.13.0 to reject such calls at compile time instead of
causing undefined behavior at runtime.
+6 -6
View File
@@ -85,15 +85,15 @@ Logarithmic in the size of the JSON object.
## See also
- [`find`](find.md) - find a value in an object
- [`contains`](contains.md) - checks whether a key exists
- [`basic_json_view::count`](../basic_json_view/count.md) - the same check on a zero-copy view
- [Element Access](../../features/element_access/index.md#does-this-key-exist) - how to test whether a key exists
- [find](find.md) find a value in an object
- [contains](contains.md) checks whether a key exists
- [basic_json_view::count](../basic_json_view/count.md) - the same check on a zero-copy view
## Version history
1. Added in version 3.11.0.
2. Added in version 1.0.0. Changed to support comparable key types in version 3.11.0. Support for keys convertible to
`std::string_view` added in version 3.13.0, consistently across the lookup functions.
2. Added in version 1.0.0. Changed parameter `key` type to `KeyType&&` in version 3.11.0. Fixed in version 3.13.0 to
consistently accept `std::string_view`-convertible keys, as already supported by [`operator[]`](operator[].md),
[`at`](at.md), [`value`](value.md), and other lookup functions.
3. Deleted overload for integral key types added in version 3.13.0 to reject such calls at compile time instead of
causing undefined behavior at runtime.
+4 -10
View File
@@ -6,13 +6,7 @@ const_reverse_iterator crbegin() const noexcept;
Returns an iterator to the reverse-beginning; that is, the last element.
<div class="nj-fig-wrap" markdown>
--8<-- "images/range-rbegin-rend.svg"
</div>
<p class="nj-caption" markdown>`crbegin()` points to the last element, like `rbegin()`, and `rend()` to the position
before the first element. The upper row is the reversed sequence and the lower row the forward sequence; dashed arrows
link each reverse iterator to the forward iterator it stores, and dashed cells are past-the-last positions.</p>
![Illustration from cppreference.com](../../images/range-rbegin-rend.svg)
## Return value
@@ -44,9 +38,9 @@ Constant.
## See also
- [`crend`](crend.md) - returns a const reverse iterator to one before the first element
- [`rbegin`](rbegin.md) - returns a reverse iterator to the last element
- [`cbegin`](cbegin.md) - returns a const iterator to the first element
- [crend](crend.md) returns a const reverse iterator to one before the first element
- [rbegin](rbegin.md) returns a reverse iterator to the last element
- [cbegin](cbegin.md) returns a const iterator to the first element
- [Iterators](../../features/iterators.md) - the article on iterators
## Version history
+4 -10
View File
@@ -7,13 +7,7 @@ const_reverse_iterator crend() const noexcept;
Returns an iterator to the reverse-end; that is, one before the first element. This element acts as a placeholder,
attempting to access it results in undefined behavior.
<div class="nj-fig-wrap" markdown>
--8<-- "images/range-rbegin-rend.svg"
</div>
<p class="nj-caption" markdown>`crend()` points to the position before the first element, like `rend()`, and `rbegin()`
to the last element. The upper row is the reversed sequence and the lower row the forward sequence; dashed arrows link
each reverse iterator to the forward iterator it stores, and dashed cells are past-the-last positions.</p>
![Illustration from cppreference.com](../../images/range-rbegin-rend.svg)
## Return value
@@ -45,9 +39,9 @@ Constant.
## See also
- [`crbegin`](crbegin.md) - returns a const reverse iterator to the last element
- [`rend`](rend.md) - returns a reverse iterator to one before the first element
- [`cend`](cend.md) - returns a const iterator to one past the last element
- [crbegin](crbegin.md) returns a const reverse iterator to the last element
- [rend](rend.md) returns a reverse iterator to one before the first element
- [cend](cend.md) returns a const iterator to one past the last element
- [Iterators](../../features/iterators.md) - the article on iterators
## Version history
@@ -32,10 +32,8 @@ The actual comparator used depends on [`object_t`](object_t.md) and can be obtai
## See also
- [`object_comparator_t`](object_comparator_t.md) - the comparator actually used by `object_t`
- [`object_t`](object_t.md) - the type used to store JSON objects
- [Template Parameter Requirements](../../features/types/template_parameters.md) - requirements on the `ObjectType` template parameter
- [Object order](../../features/object_order.md) - preserve the insertion order of keys
- [object_comparator_t](object_comparator_t.md) the comparator actually used by `object_t`
- [object_t](object_t.md) the type used to store JSON objects
## Version history
+8 -48
View File
@@ -2,28 +2,17 @@
```cpp
static basic_json diff(const basic_json& source,
const basic_json& target,
const string_t& path = "");
const basic_json& target);
```
Creates a [JSON Patch](http://jsonpatch.com) so that value `source` can be changed into the value `target` by calling
[`patch`](patch.md) function.
For two JSON values `source` and `target`, the following code yields `#!cpp true`:
For two JSON values `source` and `target`, the following code always yields `#!cpp true`:
```cpp
source.patch(diff(source, target)) == target;
```
The equality holds up to [`operator==`](operator_eq.md), so it has the following exceptions:
- A value that is not equal to itself cannot round-trip. This applies to `NaN` (also nested in an array or object) and
to [discarded](is_discarded.md) values: `diff` emits a `replace` operation for them. A `NaN` in the patch is
serialized as `#!json null`, so a patch that was dumped and parsed again would set `#!json null`.
- Numbers that compare equal produce no operation, even if their types differ or if one is zero and the other is
negative zero: `diff(1, 1.0)` (integer and floating-point), `diff(1u, 1)` (unsigned and signed integer) and
`diff(0.0, -0.0)` (positive and negative zero) all return `#!json []`. The patched value is then the `source` and
keeps its number type and sign.
## Parameters
`source` (in)
@@ -32,12 +21,6 @@ The equality holds up to [`operator==`](operator_eq.md), so it has the following
`target` (in)
: JSON value to compare against
`path` (in)
: a prefix that is put verbatim in front of the `path` member of every operation (default: `""`, which addresses the
root of the value). The prefix is neither escaped nor validated: `#!cpp diff(1, 2, "abc")` yields an operation with
the `path` `abc`, which is not a valid JSON Pointer. Use it with a valid JSON Pointer such as `/root` and escape
`~` and `/` in its reference tokens (see [JSON Pointer](../../features/json_pointer.md)).
## Return value
a JSON patch to convert the `source` to `target`
@@ -48,32 +31,11 @@ Strong guarantee: `source` and `target` are never modified.
## Complexity
Linear in the total number of values (including nested ones) in `source` and `target`, times the cost of a key-based
object operation (looking up a key in an object): logarithmic for [`json`](../json.md), and linear for
[`ordered_json`](../ordered_json.md) (see [`ordered_map` complexity](../ordered_map.md#complexity)). For
`ordered_json`, diffing two objects with `n` and `m` members therefore takes O((n+m)²) when their keys do not line up
(e.g., a key was added or the keys are in a different order). The size of the patch is proportional to the number of
operations times the length of their paths, so a small change deep inside a value yields a long `path`.
Linear in the lengths of `source` and `target`.
## Notes
- Currently, only `remove`, `add`, and `replace` operations are generated.
- The patch is correct, but not guaranteed to be minimal. For instance, `diff([1,2,3], [0,1,2,3])` yields three
`replace` operations and one `add` operation instead of a single insertion.
- Differences between two arrays are reported index by index. Elements that were added at the end of the array are added
with `add` operations on the path `/-` (appended in order), and elements that were removed are removed with `remove`
operations from the highest index down to the lowest, so that the remaining indices stay valid.
- For objects, the operations for the members of `source` come first (`replace`, `remove`, or the operations for nested
values, in the iteration order of `source`), followed by `add` operations for the members that only `target` has.
- For [`ordered_json`](../ordered_json.md), objects with the same keys in a different order are different. As a patch
cannot reorder members, `diff` removes all keys of the `source` object and adds them again in the order of the
`target`.
- If `source` and `target` differ as a whole (e.g., different types), the patch consists of a single `replace`
operation for the root of the value, i.e., with the `path` `""` (or the given `path` prefix).
- The `value` members of the patch hold copies of values of `target`. A [binary](../../features/binary_values.md) value
has no JSON representation: when a patch that contains one is serialized, it becomes an object such as
`#!json {"bytes":[1,3],"subtype":null}`, so a parsed patch no longer holds a binary value (and would set that object
instead).
Currently, only `remove`, `add`, and `replace` operations are generated.
## Examples
@@ -93,12 +55,10 @@ operations times the length of their paths, so a small change deep inside a valu
## See also
- [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902) - specification of JSON Patch
- [`patch`](patch.md) - applies a JSON Patch
- [`patch_inplace`](patch_inplace.md) - applies a JSON Patch in place
- [`merge_patch`](merge_patch.md) - applies a JSON Merge Patch
- [`merge_diff`](merge_diff.md) - creates a diff as a JSON Merge Patch
- [JSON Patch and Diff](../../features/json_patch.md) - the article on JSON Patch
- [RFC 6902 (JSON Patch)](https://tools.ietf.org/html/rfc6902)
- [patch](patch.md) applies a JSON Patch
- [patch_inplace](patch_inplace.md) applies a JSON Patch in place
- [merge_patch](merge_patch.md) applies a JSON Merge Patch
## Version history
+3 -3
View File
@@ -89,9 +89,9 @@ Binary values are serialized as an object containing two keys:
## See also
- [`to_string`](to_string.md) - returns a string representation of a JSON value
- [`operator<<`](../operator_ltlt.md) - serialize to stream
- [`basic_json_view::dump`](../basic_json_view/dump.md) - the corresponding function of `basic_json_view`, serializing
- [to_string](to_string.md) returns a string representation of a JSON value
- [operator<<](../operator_ltlt.md) serialize to stream
- [`basic_json_view::dump`](../basic_json_view/dump.md) the corresponding function of `basic_json_view`, serializing
directly from a flat index without building a `basic_json` value
- [Serialization](../../features/serialization.md) - the serialization article
+3 -3
View File
@@ -63,12 +63,12 @@ Logarithmic in the size of the container, O(log(`size()`)).
## See also
- [`emplace_back`](emplace_back.md) - add a value to an array
- [`insert`](insert.md) - add values to an array/object
- [emplace_back](emplace_back.md) add a value to an array
- [insert](insert.md) add values to an array/object
- [Modifying values](../../features/modifying_values.md) - the article on modifying values
## Version history
- Added in version 2.0.8.
- Since version 2.0.8.
- Fixed in version 3.13.0: for [`ordered_json`](../ordered_json.md), the value could previously only be passed as an
rvalue; it can now also be passed as an lvalue or a `#!cpp const` lvalue, matching the behavior of `json`.
@@ -61,11 +61,11 @@ Amortized constant.
## See also
- [`operator+=`](operator+=.md) - add a value to an array/object
- [`push_back`](push_back.md) - add a value to an array/object
- [operator+=](operator+=.md) add a value to an array/object
- [push_back](push_back.md) add a value to an array/object
- [Modifying values](../../features/modifying_values.md) - the article on modifying values
## Version history
- Added in version 2.0.8.
- Since version 2.0.8.
- Returns reference since 3.7.0.
+4 -4
View File
@@ -41,7 +41,7 @@ bool empty() const noexcept
## Notes
This function does not return whether a string stored as JSON value is empty — it returns whether the JSON container
This function does not return whether a string stored as JSON value is empty -- it returns whether the JSON container
itself is empty which is `#!cpp false` in the case of a string.
## Examples
@@ -62,9 +62,9 @@ itself is empty which is `#!cpp false` in the case of a string.
## See also
- [`size`](size.md) - returns the number of elements
- [`clear`](clear.md) - clears the content and resets the value to the default value
- [`basic_json_view::empty`](../basic_json_view/empty.md) - the same check on a zero-copy view
- [size](size.md) returns the number of elements
- [clear](clear.md) clears the content and resets the value to the default value
- [basic_json_view::empty](../basic_json_view/empty.md) - the same check on a zero-copy view
## Version history
+5 -10
View File
@@ -7,12 +7,7 @@ const_iterator end() const noexcept;
Returns an iterator to one past the last element.
<div class="nj-fig-wrap" markdown>
--8<-- "images/range-begin-end.svg"
</div>
<p class="nj-caption" markdown>`end()` points to the position after the last element and `begin()` to the first element;
the dashed cell is the past-the-last position, which must not be dereferenced.</p>
![Illustration from cppreference.com](../../images/range-begin-end.svg)
## Return value
@@ -44,11 +39,11 @@ Constant.
## See also
- [`begin`](begin.md) - returns an iterator to the first element
- [`cend`](cend.md) - returns a const iterator to one past the last element
- [`rend`](rend.md) - returns a reverse iterator to one before the first element
- [begin](begin.md) returns an iterator to the first element
- [cend](cend.md) returns a const iterator to one past the last element
- [rend](rend.md) returns a reverse iterator to one before the first element
- [Iterators](../../features/iterators.md) - the article on iterators
- [`basic_json_view::end`](../basic_json_view/end.md) - the same iteration on a zero-copy view
- [basic_json_view::end](../basic_json_view/end.md) - the same iteration on a zero-copy view
## Version history
+2 -3
View File
@@ -60,9 +60,8 @@ Constant.
## See also
- [`start_pos`](start_pos.md) - to access the start position
- [`JSON_DIAGNOSTIC_POSITIONS`](../macros/json_diagnostic_positions.md) - overview of the supported conversions
- [Parsing and Exceptions](../../features/parsing/parse_exceptions.md) - handling parse errors and locating them in the input
- [start_pos](start_pos.md) to access the start position
- [JSON_DIAGNOSTIC_POSITIONS](../macros/json_diagnostic_positions.md) for an overview of the diagnostic positions
## Version history
+5 -4
View File
@@ -204,8 +204,8 @@ Strong exception safety: if an exception occurs, the original value stays intact
## See also
- [`clear`](clear.md) - clears the contents
- [`insert`](insert.md) - add values to an array/object
- [clear](clear.md) clears the contents
- [insert](insert.md) add values to an array/object
- [Modifying values](../../features/modifying_values.md) - the article on modifying values
## Version history
@@ -213,6 +213,7 @@ Strong exception safety: if an exception occurs, the original value stays intact
1. Added in version 1.0.0. Added support for binary types in version 3.8.0.
2. Added in version 1.0.0. Added support for binary types in version 3.8.0.
3. Added in version 1.0.0.
4. Added in version 3.11.0. Support for keys convertible to `std::string_view` added in version 3.13.0, consistently
across the lookup functions.
4. Added in version 3.11.0. Fixed in version 3.13.0 to consistently accept `std::string_view`-convertible keys, as
already supported by [`operator[]`](operator[].md), [`at`](at.md), [`value`](value.md), and other lookup
functions.
5. Added in version 1.0.0.
@@ -61,7 +61,7 @@ keep
## See also
- [`dump`](dump.md) - serializes a JSON value, with an `error_handler_t` parameter to configure invalid UTF-8 handling
- [dump](dump.md) serializes a JSON value, with an `error_handler_t` parameter to configure invalid UTF-8 handling
- [Handling invalid UTF-8](../../features/serialization.md#handling-invalid-utf-8) - the article on handling invalid UTF-8
## Version history
+2 -9
View File
@@ -40,9 +40,6 @@ classDiagram
style json_exception fill:#CCCCFF
```
<p class="nj-caption" markdown>Class hierarchy of the library's exceptions; arrows point from a derived class to its
base class, and the highlighted box is `basic_json::exception`.</p>
Subclasses:
- [`parse_error`](parse_error.md) for exceptions indicating a parse error
@@ -83,12 +80,8 @@ constructor.
## See also
- [List of exceptions](../../home/exceptions.md) - overview of all exceptions thrown by the library
- [Working Without Exceptions](../../features/no_exceptions.md) - using the library without exceptions
- [`JSON_DIAGNOSTICS`](../macros/json_diagnostics.md) - extended exception messages with the path of the failing value
- [Parsing and Exceptions](../../features/parsing/parse_exceptions.md) - parsing alternatives that do not throw
- [Debugging](../../home/debugging.md) - debugging aids
[List of exceptions](../../home/exceptions.md)
## Version history
- Added in version 3.0.0.
- Since version 3.0.0.
+6 -7
View File
@@ -91,16 +91,15 @@ Logarithmic in the size of the JSON object.
## See also
- [`count`](count.md) - returns the number of occurrences of a key
- [`contains`](contains.md) - checks whether a key exists
- [`basic_json_view::find`](../basic_json_view/find.md) - the same lookup on a zero-copy view (a duplicate key resolves
to the first member, whereas `parse()` keeps the last)
- [Element Access](../../features/element_access/index.md#does-this-key-exist) - how to test whether a key exists
- [count](count.md) returns the number of occurrences of a key
- [contains](contains.md) checks whether a key exists
- [basic_json_view::find](../basic_json_view/find.md) - the same lookup on a zero-copy view
## Version history
1. Added in version 3.11.0.
2. Added in version 1.0.0. Changed to support comparable types in version 3.11.0. Support for keys convertible to
`std::string_view` added in version 3.13.0, consistently across the lookup functions.
2. Added in version 1.0.0. Changed to support comparable types in version 3.11.0. Fixed in version 3.13.0 to
consistently accept `std::string_view`-convertible keys, as already supported by [`operator[]`](operator[].md),
[`at`](at.md), [`value`](value.md), and other lookup functions.
3. Deleted overloads for integral key types added in version 3.13.0 to reject such calls at compile time instead of
causing undefined behavior at runtime.
+1 -2
View File
@@ -58,8 +58,7 @@ Empty objects and arrays are flattened to `#!json null` and will not be reconstr
## See also
- [`unflatten`](unflatten.md) - the reverse function
- [JSON Pointer](../../features/json_pointer.md#flatten-unflatten) - the article on JSON Pointer and flattening
- [unflatten](unflatten.md) the reverse function
## Version history
+2 -2
View File
@@ -86,8 +86,8 @@ std::string format_as(const BasicJsonType& j)
## See also
- [`dump`](dump.md) - serialize a JSON value to a string
- [`std::formatter<basic_json>`](std_formatter.md) - the `std::format` (C++20) equivalent
- [dump](dump.md)
- [std::formatter<basic_json>](std_formatter.md) - the `std::format` (C++20) equivalent
- [Serialization](../../features/serialization.md) - the serialization article
## Version history
+7 -14
View File
@@ -82,11 +82,8 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
- Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if a parse error occurs
- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a string could not be parsed
successfully, or if a string value or object key is not valid UTF-8 and `error_handler` is `strict`
- Throws [parse_error.115](../../home/exceptions.md#jsonexceptionparse_error115) if the text of a high-precision
number (`H`) is not a valid number
- Throws [out_of_range.408](../../home/exceptions.md#jsonexceptionout_of_range408) if the size of an optimized container
cannot be represented by `std::size_t` or exceeds the container's `max_size()`, or if the product of the dimensions of
an n-dimensional array overflows
or n-dimensional array cannot be represented by `std::size_t`
## Complexity
@@ -110,16 +107,12 @@ Linear in the size of the input.
## See also
- [BJData](../../features/binary_formats/bjdata.md) - the format, its byte layout and how values are mapped
- [Binary formats](../../features/binary_formats/index.md) - overview and comparison of the supported binary formats
- [Parsing untrusted input](../../features/parsing/untrusted_input.md) - limits and safe handling of hostile data
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [`to_bjdata`](to_bjdata.md) - create a BJData serialization of a JSON value
- [`from_cbor`](from_cbor.md) - create a JSON value from an input in CBOR format
- [`from_msgpack`](from_msgpack.md) - create a JSON value from an input in MessagePack format
- [`from_bson`](from_bson.md) - create a JSON value from an input in BSON format
- [`from_ubjson`](from_ubjson.md) - create a JSON value from an input in UBJSON format
- [`from_bon8`](from_bon8.md) - create a JSON value from an input in BON8 format
- [to_bjdata](to_bjdata.md) create a BJData serialization of a JSON value
- [from_cbor](from_cbor.md) create a JSON value from an input in CBOR format
- [from_msgpack](from_msgpack.md) create a JSON value from an input in MessagePack format
- [from_bson](from_bson.md) create a JSON value from an input in BSON format
- [from_ubjson](from_ubjson.md) create a JSON value from an input in UBJSON format
- [from_bon8](from_bon8.md) create a JSON value from an input in BON8 format
## Version history
+6 -14
View File
@@ -74,11 +74,6 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
- Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if a parse error occurs, for instance
an invalid byte, a string that is not valid UTF-8, or an object key that is not a string
The UTF-8 validity of strings is always checked, independent of
[`JSON_STRICT_BINARY_UTF8`](../macros/json_strict_binary_utf8.md), because the end of a BON8 string is determined from
its encoding. Duplicate object keys are accepted; the last value wins (see
[BON8](../../features/binary_formats/bon8.md)).
## Complexity
Linear in the size of the input.
@@ -101,15 +96,12 @@ Linear in the size of the input.
## See also
- [BON8](../../features/binary_formats/bon8.md) - the format, its byte layout and how values are mapped
- [Binary formats](../../features/binary_formats/index.md) - overview and comparison of the supported binary formats
- [Parsing untrusted input](../../features/parsing/untrusted_input.md) - limits and safe handling of hostile data
- [`to_bon8`](to_bon8.md) - create a BON8 serialization of a JSON value
- [`from_cbor`](from_cbor.md) - create a JSON value from an input in CBOR format
- [`from_msgpack`](from_msgpack.md) - create a JSON value from an input in MessagePack format
- [`from_bson`](from_bson.md) - create a JSON value from an input in BSON format
- [`from_ubjson`](from_ubjson.md) - create a JSON value from an input in UBJSON format
- [`from_bjdata`](from_bjdata.md) - create a JSON value from an input in BJData format
- [to_bon8](to_bon8.md) create a BON8 serialization of a JSON value
- [from_cbor](from_cbor.md) create a JSON value from an input in CBOR format
- [from_msgpack](from_msgpack.md) create a JSON value from an input in MessagePack format
- [from_bson](from_bson.md) create a JSON value from an input in BSON format
- [from_ubjson](from_ubjson.md) create a JSON value from an input in UBJSON format
- [from_bjdata](from_bjdata.md) create a JSON value from an input in BJData format
## Version history
+8 -13
View File
@@ -80,8 +80,7 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
- Throws [`parse_error.110`](../../home/exceptions.md#jsonexceptionparse_error110) if the given input ends prematurely or
the end of the input was not reached when `strict` was set to true
- Throws [`parse_error.112`](../../home/exceptions.md#jsonexceptionparse_error112) if a parse error occurs (e.g., an
invalid string or byte array length, an invalid inner length of a binary value with subtype `0x02`, or a document size
that does not match the content; `strict` does not affect the document size checks)
invalid string or byte array length)
- Throws [`parse_error.114`](../../home/exceptions.md#jsonexceptionparse_error114) if an unsupported BSON record type is
encountered
- Throws [`parse_error.113`](../../home/exceptions.md#jsonexceptionparse_error113) if a string value or object key is
@@ -109,17 +108,13 @@ Linear in the size of the input.
## See also
- [BSON](../../features/binary_formats/bson.md) - the format, its byte layout and how values are mapped
- [Binary formats](../../features/binary_formats/index.md) - overview and comparison of the supported binary formats
- [Parsing untrusted input](../../features/parsing/untrusted_input.md) - limits and safe handling of hostile data
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [BSON specification](http://bsonspec.org/spec.html) - specification of the BSON format
- [`to_bson`](to_bson.md) - the analogous serialization
- [`from_cbor`](from_cbor.md) - the related CBOR format
- [`from_msgpack`](from_msgpack.md) - the related MessagePack format
- [`from_ubjson`](from_ubjson.md) - the related UBJSON format
- [`from_bjdata`](from_bjdata.md) - the related BJData format
- [`from_bon8`](from_bon8.md) - the related BON8 format
- [BSON specification](http://bsonspec.org/spec.html)
- [to_bson](to_bson.md) for the analogous serialization
- [from_cbor](from_cbor.md) for the related CBOR format
- [from_msgpack](from_msgpack.md) for the related MessagePack format
- [from_ubjson](from_ubjson.md) for the related UBJSON format
- [from_bjdata](from_bjdata.md) for the related BJData format
- [from_bon8](from_bon8.md) for the related BON8 format
## Version history
+10 -22
View File
@@ -32,10 +32,8 @@ The exact mapping and its limitations are described on a [dedicated page](../../
- an `std::istream` object
- a `FILE` pointer
- a C-style array of characters (its terminating NUL is read as trailing data: `parse_error.110` unless `strict` is
`false`)
- a pointer to a null-terminated string of single byte characters (read up to the first 0x00 byte, which is a valid
CBOR byte)
- a C-style array of characters
- a pointer to a null-terminated string of single byte characters
- a container `obj` for which `begin(obj)` and `end(obj)` produce a valid pair of iterators
(as found via ADL or member functions, with semantics compatible to `std::begin` and `std::end`)
@@ -91,14 +89,8 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
- Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if unsupported features from CBOR were
used in the given input or if the input is not valid CBOR
- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a map key is not a string (keys of
other types are not supported, as JSON object keys are always strings), if the head of a string or byte string is
malformed (including a chunk of the wrong type or an indefinite-length string nested inside an indefinite-length
string), or if a string value or object key (or one chunk of an indefinite-length string) is not valid UTF-8 and
`error_handler` is `strict`
- Throws [out_of_range.408](../../home/exceptions.md#jsonexceptionout_of_range408) if an array or map announces
a length that `std::size_t` cannot hold, or that equals `std::size_t(-1)` (for example `9B FF FF FF FF FF FF FF FF`)
- Throws [out_of_range.406](../../home/exceptions.md#jsonexceptionout_of_range406) if a floating-point number does not
fit into `number_float_t`
other types are not supported, as JSON object keys are always strings), or if a string value or object key is not
valid UTF-8 and `error_handler` is `strict`
## Complexity
@@ -122,16 +114,12 @@ Linear in the size of the input.
## See also
- [CBOR](../../features/binary_formats/cbor.md) - the format, its byte layout and how values are mapped
- [Binary formats](../../features/binary_formats/index.md) - overview and comparison of the supported binary formats
- [Parsing untrusted input](../../features/parsing/untrusted_input.md) - limits and safe handling of hostile data
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [`to_cbor`](to_cbor.md) - create a CBOR serialization of a JSON value
- [`from_msgpack`](from_msgpack.md) - create a JSON value from an input in MessagePack format
- [`from_bson`](from_bson.md) - create a JSON value from an input in BSON format
- [`from_ubjson`](from_ubjson.md) - create a JSON value from an input in UBJSON format
- [`from_bjdata`](from_bjdata.md) - create a JSON value from an input in BJData format
- [`from_bon8`](from_bon8.md) - create a JSON value from an input in BON8 format
- [to_cbor](to_cbor.md) create a CBOR serialization of a JSON value
- [from_msgpack](from_msgpack.md) create a JSON value from an input in MessagePack format
- [from_bson](from_bson.md) create a JSON value from an input in BSON format
- [from_ubjson](from_ubjson.md) create a JSON value from an input in UBJSON format
- [from_bjdata](from_bjdata.md) create a JSON value from an input in BJData format
- [from_bon8](from_bon8.md) create a JSON value from an input in BON8 format
## Version history
@@ -107,16 +107,12 @@ Linear in the size of the input.
## See also
- [MessagePack](../../features/binary_formats/messagepack.md) - the format, its byte layout and how values are mapped
- [Binary formats](../../features/binary_formats/index.md) - overview and comparison of the supported binary formats
- [Parsing untrusted input](../../features/parsing/untrusted_input.md) - limits and safe handling of hostile data
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [`to_msgpack`](to_msgpack.md) - create a MessagePack serialization of a JSON value
- [`from_cbor`](from_cbor.md) - create a JSON value from an input in CBOR format
- [`from_bson`](from_bson.md) - create a JSON value from an input in BSON format
- [`from_ubjson`](from_ubjson.md) - create a JSON value from an input in UBJSON format
- [`from_bjdata`](from_bjdata.md) - create a JSON value from an input in BJData format
- [`from_bon8`](from_bon8.md) - create a JSON value from an input in BON8 format
- [to_msgpack](to_msgpack.md) create a MessagePack serialization of a JSON value
- [from_cbor](from_cbor.md) create a JSON value from an input in CBOR format
- [from_bson](from_bson.md) create a JSON value from an input in BSON format
- [from_ubjson](from_ubjson.md) create a JSON value from an input in UBJSON format
- [from_bjdata](from_bjdata.md) create a JSON value from an input in BJData format
- [from_bon8](from_bon8.md) create a JSON value from an input in BON8 format
## Version history
+10 -21
View File
@@ -79,18 +79,11 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
- Throws [parse_error.110](../../home/exceptions.md#jsonexceptionparse_error110) if the given input ends prematurely or
the end of the file was not reached when `strict` was set to true
- Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if an invalid type marker is read
(including a type marker after `$` of an optimized container, even if its count is 0), or if `$` is not followed by `#`
- Throws [parse_error.112](../../home/exceptions.md#jsonexceptionparse_error112) if a parse error occurs
- Throws [parse_error.113](../../home/exceptions.md#jsonexceptionparse_error113) if a string could not be parsed
successfully (negative or non-integer length, `C` followed by a byte above 0x7F), if the count of an optimized
container is negative, or if a string value or object key is not valid UTF-8 and `error_handler` is `strict`
- Throws [parse_error.115](../../home/exceptions.md#jsonexceptionparse_error115) if the text of a high-precision number
(`H`) is not a valid JSON number
- Throws [out_of_range.406](../../home/exceptions.md#jsonexceptionout_of_range406) if a high-precision number, or a
float64 when `number_float_t` is `float`, does not fit into `number_float_t`
- Throws [out_of_range.408](../../home/exceptions.md#jsonexceptionout_of_range408) if the count of an optimized
container exceeds the capacity of the container (or of `std::size_t`), or if an optimized array of `Z`, `T`, or `F` has
more than 1,048,576 elements
successfully, or if a string value or object key is not valid UTF-8 and `error_handler` is `strict`
- Throws [out_of_range.408](../../home/exceptions.md#jsonexceptionout_of_range408) if the size of an optimized container
or n-dimensional array cannot be represented by `std::size_t`
## Complexity
@@ -114,16 +107,12 @@ Linear in the size of the input.
## See also
- [UBJSON](../../features/binary_formats/ubjson.md) - the format, its byte layout and how values are mapped
- [Binary formats](../../features/binary_formats/index.md) - overview and comparison of the supported binary formats
- [Parsing untrusted input](../../features/parsing/untrusted_input.md) - limits and safe handling of hostile data
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [`to_ubjson`](to_ubjson.md) - create a UBJSON serialization of a JSON value
- [`from_cbor`](from_cbor.md) - create a JSON value from an input in CBOR format
- [`from_msgpack`](from_msgpack.md) - create a JSON value from an input in MessagePack format
- [`from_bson`](from_bson.md) - create a JSON value from an input in BSON format
- [`from_bjdata`](from_bjdata.md) - create a JSON value from an input in BJData format
- [`from_bon8`](from_bon8.md) - create a JSON value from an input in BON8 format
- [to_ubjson](to_ubjson.md) create a UBJSON serialization of a JSON value
- [from_cbor](from_cbor.md) create a JSON value from an input in CBOR format
- [from_msgpack](from_msgpack.md) create a JSON value from an input in MessagePack format
- [from_bson](from_bson.md) create a JSON value from an input in BSON format
- [from_bjdata](from_bjdata.md) create a JSON value from an input in BJData format
- [from_bon8](from_bon8.md) create a JSON value from an input in BON8 format
## Version history
+3 -5
View File
@@ -50,12 +50,10 @@ Constant.
## See also
- [`back`](back.md) - to access the last element
- [`basic_json_view::front`](../basic_json_view/front.md) - the same access on a zero-copy view (document order, not
sorted; duplicate keys are visited)
- [Element Access](../../features/element_access/index.md) - overview of all ways to access elements
- [back](back.md) to access the last element
- [basic_json_view::front](../basic_json_view/front.md) - the same access on a zero-copy view
## Version history
- Added in version 1.0.0.
- Binary values are supported since version 3.8.0.
- Adjusted code to return reference to binary values in version 3.8.0.
+8 -9
View File
@@ -178,17 +178,16 @@ overload (3).
## See also
- [`get_to`](get_to.md) - convert and write into a passed value
- [`get_ptr`](get_ptr.md) - get a pointer to the stored value
- [`get_ref`](get_ref.md) - get a reference to the stored value
- [`operator ValueType`](operator_ValueType.md) - get a value via implicit conversion
- [get_to](get_to.md) convert and write into a passed value
- [get_ptr](get_ptr.md) get a pointer to the stored value
- [get_ref](get_ref.md) get a reference to the stored value
- [operator ValueType](operator_ValueType.md) get a value via implicit conversion
- [Converting values](../../features/conversions.md) - the type conversions article
- [`basic_json_view::get`](../basic_json_view/get.md) - the same conversion on a zero-copy view (many types are
- [basic_json_view::get](../basic_json_view/get.md) - the same conversion on a zero-copy view (many types are
converted without ever building a `basic_json` value)
- [Arbitrary Type Conversions](../../features/arbitrary_types.md) - make your own types usable with `get`
## Version history
1. Added in version 2.1.0.
2. Added in version 2.1.0. Extended to work with other specializations of `basic_json` in version 3.1.2.
3. Added in version 1.0.0.
1. Since version 2.1.0.
2. Since version 2.1.0. Extended to work with other specializations of `basic_json` in version 3.2.0.
3. Since version 1.0.0.
@@ -36,7 +36,7 @@ Constant.
## See also
- [`basic_json`](index.md#template-parameters) - the class template, with `AllocatorType` as one of its template parameters
- [basic_json](index.md#template-parameters) the class template, with `AllocatorType` as one of its template parameters
- [Template Parameter Requirements](../../features/types/template_parameters.md#allocatortype) - the requirements for `AllocatorType`
## Version history
@@ -42,11 +42,8 @@ Constant.
## See also
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [`binary`](binary.md) - create a binary value
- [`is_binary`](is_binary.md) - check whether a value is binary
- [`get`](get.md) - get a value (explicit conversion)
- [`get_ref`](get_ref.md) - get a reference to the stored value
- [get](get.md) get a value (explicit conversion)
- [get_ref](get_ref.md) get a reference to the stored value
## Version history
+2 -3
View File
@@ -45,7 +45,7 @@ Constant.
#include <iostream>
#include <nlohmann/json.hpp>
using nlohmann::json;
using json = nlohmann::json;
int main()
{
@@ -86,8 +86,7 @@ Constant.
## See also
- [`get_ref()`](get_ref.md) - get a reference value
- [Converting values](../../features/conversions.md) - getting values out, with or without copying
- [get_ref()](get_ref.md) get a reference value
## Version history
+2 -3
View File
@@ -60,10 +60,9 @@ Constant.
## See also
- [`get_ptr()`](get_ptr.md) - get a pointer value
- [`basic_json_view::get_string`](../basic_json_view/get_string.md) - the closest counterpart on a zero-copy view: a
- [get_ptr()](get_ptr.md) get a pointer value
- [basic_json_view::get_string](../basic_json_view/get_string.md) - the closest counterpart on a zero-copy view: a
string without a copy, but as a view rather than a reference to a value that must already exist
- [Converting values](../../features/conversions.md) - getting values out, with or without copying
## Version history
+5 -6
View File
@@ -68,14 +68,13 @@ Depends on the `json_serializer<ValueType>::from_json()` implementation.
## See also
- [`get`](get.md) - get a value (explicit conversion)
- [`get_ref`](get_ref.md) - get a reference to the stored value
- [`get_ptr`](get_ptr.md) - get a pointer to the stored value
- [get](get.md) get a value (explicit conversion)
- [get_ref](get_ref.md) get a reference to the stored value
- [get_ptr](get_ptr.md) get a pointer to the stored value
- [Converting values](../../features/conversions.md) - the type conversions article
- [`basic_json_view::get_to`](../basic_json_view/get_to.md) - the same conversion on a zero-copy view
- [Arbitrary Type Conversions](../../features/arbitrary_types.md) - make your own types usable with `get_to`
- [basic_json_view::get_to](../basic_json_view/get_to.md) - the same conversion on a zero-copy view
## Version history
- Added in version 3.3.0.
- Since version 3.3.0.
- Added a `static_assert` with a clear message for `const` arguments in version 3.13.0.
+4 -30
View File
@@ -44,22 +44,6 @@ are collected in [Template Parameter Requirements](../../features/types/template
- [**json**](../json.md) - default specialization
- [**ordered_json**](../ordered_json.md) - a specialization that maintains the insertion order of object keys
## Documents and views
Besides `basic_json`, the library offers a second way to hold a parsed JSON text: a
[`basic_json_document`](../basic_json_document/index.md), which owns or borrows the text and holds a flat index of the
values in it, and a [`basic_json_view`](../basic_json_view/index.md), a read-only handle to one value of such a document.
Both are defined in the header `<nlohmann/json_view.hpp>`; see
[Zero-copy JSON views](../../features/json_view.md) for the concept and the trade-offs.
- [**json_document**](../json_document.md) / [**ordered_json_document**](../ordered_json_document.md) - read-only
documents of the `basic_json` specialization they belong to
- [**json_editable_document**](../json_editable_document.md) /
[**ordered_json_editable_document**](../ordered_json_editable_document.md) - documents that can be modified in place
- [**json_view**](../json_view.md) / [**ordered_json_view**](../ordered_json_view.md) - views of a document
- [**json_editable_view**](../json_editable_view.md) /
[**ordered_json_editable_view**](../ordered_json_editable_view.md) - views of an editable document
## Iterator invalidation
All operations that add values to an **array** ([`push_back`](push_back.md) , [`operator+=`](operator+=.md),
@@ -101,7 +85,7 @@ The class satisfies the following concept requirements:
- [EqualityComparable](https://en.cppreference.com/w/cpp/named_req/EqualityComparable): JSON values can be compared with
`==`, see [`operator==`](operator_eq.md).
- [LessThanComparable](https://en.cppreference.com/w/cpp/named_req/LessThanComparable): JSON values can be compared with
`<`, see [`operator<`](operator_lt.md).
`<`, see [`operator<`](operator_le.md).
- [Swappable](https://en.cppreference.com/w/cpp/named_req/Swappable): Any JSON lvalue or rvalue of can be swapped with
any lvalue or rvalue of other compatible types, using unqualified function `swap`.
- [NullablePointer](https://en.cppreference.com/w/cpp/named_req/NullablePointer): JSON values can be compared against
@@ -121,7 +105,6 @@ The class satisfies the following concept requirements:
- [**json_pointer**](../json_pointer/index.md) - JSON Pointer implementation
- [**json_serializer**](json_serializer.md) - type of the serializer to for conversions from/to JSON
- [**error_handler_t**](error_handler_t.md) - type to choose behavior on decoding errors
- [**bjdata_version_t**](bjdata_version_t.md) - type to choose the BJData version to write
- [**cbor_tag_handler_t**](cbor_tag_handler_t.md) - type to choose how to handle CBOR tags
- **initializer_list_t** - type for initializer lists of `basic_json` values
- [**input_format_t**](input_format_t.md) - type to choose the format to parse
@@ -189,7 +172,7 @@ The class satisfies the following concept requirements:
Functions to inspect the type of a JSON value.
- [**type**](type.md) - return the type of the JSON value
- [`operator value_t`](operator_value_t.md) - return the type of the JSON value
- [**operator value_t**](operator_value_t.md) - return the type of the JSON value
- [**type_name**](type_name.md) - return the type as string
- [**is_primitive**](is_primitive.md) - return whether the type is primitive
- [**is_structured**](is_structured.md) - return whether the type is structured
@@ -218,7 +201,7 @@ Direct access to the stored value of a JSON value.
- [**get_to**](get_to.md) - get a value and write it to a destination
- [**get_ptr**](get_ptr.md) - get a pointer value
- [**get_ref**](get_ref.md) - get a reference value
- [`operator ValueType`](operator_ValueType.md) - get a value
- [**operator ValueType**](operator_ValueType.md) - get a value
- [**get_binary**](get_binary.md) - get a binary value
- [**as_base_class**](as_base_class.md) - access the custom base class
@@ -302,7 +285,6 @@ Access to the JSON value
### JSON Merge Patch functions
- [**merge_patch**](merge_patch.md) - applies a JSON Merge Patch
- [**merge_diff**](merge_diff.md) (_static_) - creates a diff as a JSON Merge Patch
## Static functions
@@ -359,15 +341,7 @@ Access to the JSON value
## See also
- [RFC 8259: The JavaScript Object Notation (JSON) Data Interchange Format](https://tools.ietf.org/html/rfc8259) -
specification of the JSON data interchange format
- [`basic_json_document`](../basic_json_document/index.md) - / [`basic_json_view`](../basic_json_view/index.md) - parse a JSON
text into a flat index and read it through a view
- [Zero-copy JSON views](../../features/json_view.md) - when to use a document and a view instead of a `basic_json`
- [Types](../../features/types/index.md) - how JSON values are stored and which types exist
- [Converting values](../../features/conversions.md) - get values out of a JSON value and put values in
- [Creating JSON values](../../features/creating_values.md) - all the ways to build a JSON value
- [Arbitrary Type Conversions](../../features/arbitrary_types.md) - convert your own types to and from JSON
- [RFC 8259: The JavaScript Object Notation (JSON) Data Interchange Format](https://tools.ietf.org/html/rfc8259)
## Version history
@@ -53,9 +53,8 @@ bon8
## See also
- [`sax_parse`](sax_parse.md) - generic SAX parse interface, taking an `input_format_t` to select the input format
- [`cbor_tag_handler_t`](cbor_tag_handler_t.md) - configures how CBOR tags are treated while parsing
- [Binary Formats](../../features/binary_formats/index.md) - CBOR, MessagePack, BSON, and other formats
- [sax_parse](sax_parse.md) generic SAX parse interface, taking an `input_format_t` to select the input format
- [cbor_tag_handler_t](cbor_tag_handler_t.md) configures how CBOR tags are treated while parsing
## Version history
+4 -5
View File
@@ -185,11 +185,10 @@ Strong exception safety: if an exception occurs, the original value stays intact
## See also
- [`emplace`](emplace.md) - add a value to an object
- [`emplace_back`](emplace_back.md) - add a value to an array
- [`push_back`](push_back.md) - add a value to an array/object
- [`update`](update.md) - merges objects
- [Modifying values](../../features/modifying_values.md) - the article on modifying values
- [emplace](emplace.md) add a value to an object
- [emplace_back](emplace_back.md) add a value to an array
- [push_back](push_back.md) add a value to an array/object
- [update](update.md) merges objects
## Version history
@@ -40,9 +40,6 @@ classDiagram
style json_invalid_iterator fill:#CCCCFF
```
<p class="nj-caption" markdown>Class hierarchy of the library's exceptions; arrows point from a derived class to its
base class, and the highlighted box is `basic_json::invalid_iterator`.</p>
## Member functions
- **what** - returns explanatory string
@@ -69,15 +66,13 @@ base class, and the highlighted box is `basic_json::invalid_iterator`.</p>
## See also
- [`exception`](exception.md) - the base class of all exceptions thrown by the library
- [List of iterator errors](../../home/exceptions.md#iterator-errors) - overview of iterator errors (`invalid_iterator`)
- [`parse_error`](parse_error.md) - exceptions indicating a parse error
- [`type_error`](type_error.md) - exceptions indicating executing a member function with a wrong type
- [`out_of_range`](out_of_range.md) - exceptions indicating access out of the defined range
- [`other_error`](other_error.md) - exceptions indicating other library errors
- [Exceptions](../../home/exceptions.md) - all exceptions and their error codes
- [`JSON_DIAGNOSTICS`](../macros/json_diagnostics.md) - extended exception messages with the path of the failing value
- [`exception`](exception.md) for the base class of all exceptions thrown by the library
- [List of iterator errors](../../home/exceptions.md#iterator-errors)
- [`parse_error`](parse_error.md) for exceptions indicating a parse error
- [`type_error`](type_error.md) for exceptions indicating executing a member function with a wrong type
- [`out_of_range`](out_of_range.md) for exceptions indicating access out of the defined range
- [`other_error`](other_error.md) for exceptions indicating other library errors
## Version history
- Added in version 3.0.0.
- Since version 3.0.0.
+5 -6
View File
@@ -36,12 +36,11 @@ Constant.
## See also
- [`is_object`](is_object.md) - checks whether the JSON value is an object
- [`is_structured`](is_structured.md) - checks whether the JSON value is structured (array or object)
- [`type`](type.md) - returns the type of the JSON value
- [`array_t`](array_t.md) - the type used to store JSON arrays
- [`basic_json_view::is_array`](../basic_json_view/is_array.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [is_object](is_object.md) checks whether the JSON value is an object
- [is_structured](is_structured.md) checks whether the JSON value is structured (array or object)
- [type](type.md) returns the type of the JSON value
- [array_t](array_t.md) the type used to store JSON arrays
- [basic_json_view::is_array](../basic_json_view/is_array.md) - the same check on a zero-copy view
## Version history
+4 -5
View File
@@ -36,11 +36,10 @@ Constant.
## See also
- [Binary values](../../features/binary_values.md) - how binary values and subtypes are handled
- [`is_primitive`](is_primitive.md) - checks whether the JSON value is primitive
- [`binary_t`](binary_t.md) - the type used to store binary values
- [`get_binary`](get_binary.md) - returns a reference to the stored binary value
- [`basic_json_view::is_binary`](../basic_json_view/is_binary.md) - the same check on a zero-copy view
- [is_primitive](is_primitive.md) checks whether the JSON value is primitive
- [binary_t](binary_t.md) the type used to store binary values
- [get_binary](get_binary.md) returns a reference to the stored binary value
- [basic_json_view::is_binary](../basic_json_view/is_binary.md) - the same check on a zero-copy view
## Version history
@@ -36,10 +36,9 @@ Constant.
## See also
- [`boolean_t`](boolean_t.md) - the type used to store JSON booleans
- [`is_primitive`](is_primitive.md) - checks whether the JSON value is primitive
- [`basic_json_view::is_boolean`](../basic_json_view/is_boolean.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [boolean_t](boolean_t.md) the type used to store JSON booleans
- [is_primitive](is_primitive.md) checks whether the JSON value is primitive
- [basic_json_view::is_boolean](../basic_json_view/is_boolean.md) - the same check on a zero-copy view
## Version history
@@ -87,9 +87,8 @@ with `allow_exceptions` set to `#!cpp false`: a parse error then yields a discar
## See also
- [`basic_json_view::is_discarded`](../basic_json_view/is_discarded.md) - the corresponding check on a zero-copy view,
- [basic_json_view::is_discarded](../basic_json_view/is_discarded.md) - the corresponding check on a zero-copy view,
which is `#!cpp true` if the view refers to no value
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
## Version history
+5 -6
View File
@@ -36,12 +36,11 @@ Constant.
## See also
- [`is_array`](is_array.md) - checks whether the JSON value is an array
- [`is_object`](is_object.md) - checks whether the JSON value is an object
- [`type`](type.md) - returns the type of the JSON value
- [`value_t`](value_t.md) - the enumeration of JSON types
- [`basic_json_view::is_null`](../basic_json_view/is_null.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [is_array](is_array.md) checks whether the JSON value is an array
- [is_object](is_object.md) checks whether the JSON value is an object
- [type](type.md) returns the type of the JSON value
- [value_t](value_t.md) the enumeration of JSON types
- [basic_json_view::is_null](../basic_json_view/is_null.md) - the same check on a zero-copy view
## Version history
+4 -6
View File
@@ -46,12 +46,10 @@ constexpr bool is_number() const noexcept
## See also
- [`is_number_integer()`](is_number_integer.md) - check if the value is an integer or unsigned integer number
- [`is_number_unsigned()`](is_number_unsigned.md) - check if the value is an unsigned integer number
- [`is_number_float()`](is_number_float.md) - check if the value is a floating-point number
- [`basic_json_view::is_number`](../basic_json_view/is_number.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [Number Handling](../../features/types/number_handling.md) - how numbers are stored and converted
- [is_number_integer()](is_number_integer.md) check if the value is an integer or unsigned integer number
- [is_number_unsigned()](is_number_unsigned.md) check if the value is an unsigned integer number
- [is_number_float()](is_number_float.md) check if the value is a floating-point number
- [basic_json_view::is_number](../basic_json_view/is_number.md) - the same check on a zero-copy view
## Version history
@@ -37,12 +37,10 @@ Constant.
## See also
- [`is_number()`](is_number.md) - check if the value is a number
- [`is_number_integer()`](is_number_integer.md) - check if the value is an integer or unsigned integer number
- [`is_number_unsigned()`](is_number_unsigned.md) - check if the value is an unsigned integer number
- [`basic_json_view::is_number_float`](../basic_json_view/is_number_float.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [Number Handling](../../features/types/number_handling.md) - how numbers are stored and converted
- [is_number()](is_number.md) check if the value is a number
- [is_number_integer()](is_number_integer.md) check if the value is an integer or unsigned integer number
- [is_number_unsigned()](is_number_unsigned.md) check if the value is an unsigned integer number
- [basic_json_view::is_number_float](../basic_json_view/is_number_float.md) - the same check on a zero-copy view
## Version history
@@ -37,12 +37,10 @@ Constant.
## See also
- [`is_number()`](is_number.md) - check if the value is a number
- [`is_number_unsigned()`](is_number_unsigned.md) - check if the value is an unsigned integer number
- [`is_number_float()`](is_number_float.md) - check if the value is a floating-point number
- [`basic_json_view::is_number_integer`](../basic_json_view/is_number_integer.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [Number Handling](../../features/types/number_handling.md) - how numbers are stored and converted
- [is_number()](is_number.md) check if the value is a number
- [is_number_unsigned()](is_number_unsigned.md) check if the value is an unsigned integer number
- [is_number_float()](is_number_float.md) check if the value is a floating-point number
- [basic_json_view::is_number_integer](../basic_json_view/is_number_integer.md) - the same check on a zero-copy view
## Version history
@@ -6,9 +6,6 @@ constexpr bool is_number_unsigned() const noexcept;
This function returns `#!cpp true` if and only if the JSON value is an unsigned integer number. This excludes
floating-point and signed integer values.
If [`number_unsigned_t`](number_unsigned_t.md) is the same type as [`number_integer_t`](number_integer_t.md), every
integer is stored as `number_integer_t`, and this function always returns `#!cpp false`.
## Return value
@@ -40,12 +37,10 @@ Constant.
## See also
- [`is_number()`](is_number.md) - check if the value is a number
- [`is_number_integer()`](is_number_integer.md) - check if the value is an integer or unsigned integer number
- [`is_number_float()`](is_number_float.md) - check if the value is a floating-point number
- [`basic_json_view::is_number_unsigned`](../basic_json_view/is_number_unsigned.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [Number Handling](../../features/types/number_handling.md) - how numbers are stored and converted
- [is_number()](is_number.md) check if the value is a number
- [is_number_integer()](is_number_integer.md) check if the value is an integer or unsigned integer number
- [is_number_float()](is_number_float.md) check if the value is a floating-point number
- [basic_json_view::is_number_unsigned](../basic_json_view/is_number_unsigned.md) - the same check on a zero-copy view
## Version history
+5 -6
View File
@@ -36,12 +36,11 @@ Constant.
## See also
- [`is_array`](is_array.md) - checks whether the JSON value is an array
- [`is_structured`](is_structured.md) - checks whether the JSON value is structured (array or object)
- [`type`](type.md) - returns the type of the JSON value
- [`object_t`](object_t.md) - the type used to store JSON objects
- [`basic_json_view::is_object`](../basic_json_view/is_object.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [is_array](is_array.md) checks whether the JSON value is an array
- [is_structured](is_structured.md) checks whether the JSON value is structured (array or object)
- [type](type.md) returns the type of the JSON value
- [object_t](object_t.md) the type used to store JSON objects
- [basic_json_view::is_object](../basic_json_view/is_object.md) - the same check on a zero-copy view
## Version history
@@ -56,14 +56,13 @@ This library extends primitive types to binary types, because binary types are r
## See also
- [`is_structured()`](is_structured.md) - returns whether the JSON value is structured
- [`is_null()`](is_null.md) - returns whether the JSON value is `null`
- [`is_string()`](is_string.md) - returns whether the JSON value is a string
- [`is_boolean()`](is_boolean.md) - returns whether the JSON value is a boolean
- [`is_number()`](is_number.md) - returns whether the JSON value is a number
- [`is_binary()`](is_binary.md) - returns whether the JSON value is a binary array
- [`basic_json_view::is_primitive`](../basic_json_view/is_primitive.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [is_structured()](is_structured.md) returns whether the JSON value is structured
- [is_null()](is_null.md) returns whether the JSON value is `null`
- [is_string()](is_string.md) returns whether the JSON value is a string
- [is_boolean()](is_boolean.md) returns whether the JSON value is a boolean
- [is_number()](is_number.md) returns whether the JSON value is a number
- [is_binary()](is_binary.md) returns whether the JSON value is a binary array
- [basic_json_view::is_primitive](../basic_json_view/is_primitive.md) - the same check on a zero-copy view
## Version history
+4 -5
View File
@@ -36,11 +36,10 @@ Constant.
## See also
- [`is_primitive`](is_primitive.md) - checks whether the JSON value is primitive
- [`type`](type.md) - returns the type of the JSON value
- [`string_t`](string_t.md) - the type used to store JSON strings
- [`basic_json_view::is_string`](../basic_json_view/is_string.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [is_primitive](is_primitive.md) checks whether the JSON value is primitive
- [type](type.md) returns the type of the JSON value
- [string_t](string_t.md) the type used to store JSON strings
- [basic_json_view::is_string](../basic_json_view/is_string.md) - the same check on a zero-copy view
## Version history
@@ -54,11 +54,10 @@ Note that though strings are containers in C++, they are treated as primitive va
## See also
- [`is_primitive()`](is_primitive.md) - returns whether JSON value is primitive
- [`is_array()`](is_array.md) - returns whether the value is an array
- [`is_object()`](is_object.md) - returns whether the value is an object
- [`basic_json_view::is_structured`](../basic_json_view/is_structured.md) - the same check on a zero-copy view
- [Types](../../features/types/index.md) - the JSON value types and how they are stored
- [is_primitive()](is_primitive.md) returns whether JSON value is primitive
- [is_array()](is_array.md) returns whether the value is an array
- [is_object()](is_object.md) returns whether the value is an object
- [basic_json_view::is_structured](../basic_json_view/is_structured.md) - the same check on a zero-copy view
## Version history
+7 -8
View File
@@ -54,7 +54,7 @@ using element_type = decltype(*j_object.items().begin());
```
The per-element type (`iteration_proxy_value`) lives in the library's internal `detail` namespace and is
intentionally unspecified as a stable, named type — `decltype` is the supported way to obtain it, but its exact
intentionally unspecified as a stable, named type -- `decltype` is the supported way to obtain it, but its exact
name/definition may change between versions.
## Return value
@@ -97,16 +97,15 @@ When iterating over an array, `key()` will return the index of the element as st
## See also
- [`begin`](begin.md) - returns an iterator to the first element
- [`end`](end.md) - returns an iterator to one past the last element
- [`basic_json_view::items`](../basic_json_view/items.md) - the same range on a zero-copy view (`#!cpp const auto`,
not `#!cpp const auto&`: items are produced on the fly; document order, not sorted; duplicate keys are visited)
- [Iterators](../../features/iterators.md#access-object-keys-during-iteration) - the article on iterating over keys and values
- [begin](begin.md) returns an iterator to the first element
- [end](end.md) returns an iterator to one past the last element
- [basic_json_view::items](../basic_json_view/items.md) - the same range on a zero-copy view (`#!cpp const auto`,
not `#!cpp const auto&`: items are produced on the fly)
## Version history
- Added in version 3.1.0 as the replacement of the static function `iterator_wrapper`, which was available since
version 1.0.0 and is deprecated since version 3.1.0.
- Added `iterator_wrapper` in version 3.0.0.
- Added `items` and deprecated `iterator_wrapper` in version 3.1.0.
- Added structured binding support in version 3.5.0.
!!! warning "Deprecation"
@@ -57,7 +57,7 @@ same name. Hidden members remain accessible via [`as_base_class`](as_base_class.
## See also
- [`as_base_class`](as_base_class.md) - access the custom base class
- [as_base_class](as_base_class.md) - access the custom base class
- [Template Parameter Requirements](../../features/types/template_parameters.md#custombaseclass) - the requirements for `CustomBaseClass`
## Version history
@@ -44,12 +44,11 @@ deserializes. See [Template Parameter Requirements](../../features/types/templat
## See also
- [`adl_serializer`](../adl_serializer/index.md) - the default `json_serializer`
- [`get`](get.md) - explicit type conversion using the `json_serializer`'s `from_json()` method
- [`get_to`](get_to.md) - explicit type conversion into a variable using the `json_serializer`'s `from_json()` method
- [adl_serializer](../adl_serializer/index.md) the default `json_serializer`
- [get](get.md) explicit type conversion using the `json_serializer`'s `from_json()` method
- [get_to](get_to.md) explicit type conversion into a variable using the `json_serializer`'s `from_json()` method
- [Arbitrary Type Conversions](../../features/arbitrary_types.md) - the article on converting between JSON values and arbitrary types
- [Template Parameter Requirements](../../features/types/template_parameters.md) - requirements on the `JSONSerializer` template parameter
## Version history
- Added in version 2.1.0.
- Since version 2.0.0.
+4 -4
View File
@@ -33,7 +33,7 @@ constant complexity.
## Notes
This function does not return the maximal length of a string stored as JSON value — it returns the maximal number of
This function does not return the maximal length of a string stored as JSON value -- it returns the maximal number of
string elements the JSON value can store which is `1`.
## Examples
@@ -56,9 +56,9 @@ string elements the JSON value can store which is `1`.
## See also
- [`size`](size.md) - returns the number of elements
- [`array_t`](array_t.md) - the type used to store JSON arrays
- [`object_t`](object_t.md) - the type used to store JSON objects
- [size](size.md) returns the number of elements
- [array_t](array_t.md) the type used to store JSON arrays
- [object_t](object_t.md) the type used to store JSON objects
## Version history
@@ -1,80 +0,0 @@
# <small>nlohmann::basic_json::</small>merge_diff
```cpp
static basic_json merge_diff(const basic_json& source,
const basic_json& target);
```
Creates a [JSON Merge Patch](https://tools.ietf.org/html/rfc7396) so that value `source` can be changed into the value
`target` by calling the [`merge_patch`](merge_patch.md) function. The patch contains only what differs: changed and
added members with their new values, and removed members with the value `#!json null`. Nested objects are compared
member by member; any other value that differs, including an array, is replaced as a whole.
For two JSON values `source` and `target`, where `target` contains no object member whose value is `#!json null`, the
following code always yields `#!cpp true` (for [`ordered_json`](../ordered_json.md), see the notes below):
```cpp
basic_json patched = source;
patched.merge_patch(merge_diff(source, target));
patched == target;
```
## Parameters
`source` (in)
: JSON value to compare from
`target` (in)
: JSON value to compare against
## Return value
a JSON Merge Patch to convert the `source` to `target`
## Exception safety
Strong guarantee: `source` and `target` are never modified.
## Complexity
Linear in the total number of values (including nested ones) in `source` and `target`, times the cost of a key-based
object operation (looking up a key, or adding one to the patch): logarithmic for [`json`](../json.md), and linear for
[`ordered_json`](../ordered_json.md) (see [`ordered_map` complexity](../ordered_map.md#complexity)). For
`ordered_json`, diffing two objects with `n` and `m` members therefore takes O((n+m)²).
## Notes
- A merge patch uses `#!json null` to remove a member, so it cannot set a member to `#!json null`. As in RFC 7396, a
`#!json null` member of `target` is treated as absent: the patch removes the member from `source` instead of setting
it to `#!json null`. A member that is `#!json null` in both `source` and `target` is unchanged and left out of the
patch, so `source` keeps it.
- A merge patch cannot reorder object members, and [`merge_patch`](merge_patch.md) appends added members at the end.
For [`ordered_json`](../ordered_json.md), the patched value therefore has the same members as `target`, but not
necessarily in the same order, and may compare unequal to it. The patch lists changed and removed members in the
order of `source`, followed by added members in the order of `target`.
## Examples
??? example
The following code shows how a JSON Merge Patch is created as a diff for two JSON values.
```cpp
--8<-- "examples/merge_diff.cpp"
```
Output:
```json
--8<-- "examples/merge_diff.output"
```
## See also
- [RFC 7396 (JSON Merge Patch)](https://tools.ietf.org/html/rfc7396) - specification of JSON Merge Patch
- [`merge_patch`](merge_patch.md) - applies a JSON Merge Patch
- [`diff`](diff.md) - creates a diff as a JSON Patch
- [JSON Merge Patch](../../features/merge_patch.md) - the article on JSON Merge Patch
## Version history
- Added in version 3.13.0.
+7 -29
View File
@@ -39,33 +39,13 @@ Basic guarantee: if an exception is thrown during the operation, the JSON value
## Complexity
Linear in the total number of values (including nested ones) in `apply_patch`, times the cost of a key-based object
operation (looking up, adding, or erasing a member): logarithmic for [`json`](../json.md), and linear for
[`ordered_json`](../ordered_json.md) (see [`ordered_map` complexity](../ordered_map.md#complexity)). For
`ordered_json`, patching an object that has `n` members with a patch that has `m` members therefore takes O(n·m). The
cost also includes one copy of `apply_patch` (see the notes below).
Linear in the lengths of `apply_patch`.
## Notes
- `apply_patch` may be `#!cpp *this` itself or refer to a value contained in `#!cpp *this` (for example, a subobject
returned by `#!cpp (*this)[key]`); it is read as it was when `merge_patch()` was called, before any modification of
`#!cpp *this`. To make this possible, the function copies `apply_patch` before it modifies `#!cpp *this`, so the cost
includes one copy of the patch.
- A merge patch uses `#!json null` to remove a member, so it cannot set a member to `#!json null`: applying
`#!json {"a":null}` to `#!json {"a":1}` gives `#!json {}`.
- Arrays are not merged: an array in the patch replaces the target value as a whole, and a `#!json null` inside an
array is kept as an element. `#!json null` members of the target that the patch does not mention are preserved.
- A `#!json null` in the patch only removes a member; it does not prevent the creation of the enclosing objects.
Applying `#!json {"a":{"b":null}}` to `#!json {}` gives `#!json {"a":{}}` (see example 15 in Appendix A of the RFC).
- If `apply_patch` is not an object, it replaces the target as a whole. In particular, a `#!json null` patch turns the
target into `#!json null`. If `apply_patch` is an object and the target is not, the target is first replaced by an
empty object, so applying `#!json {}` to `#!json 1` gives `#!json {}`.
- A merge patch cannot express every change; for example, it cannot reorder array elements or remove a specific array
element. Use [JSON Patch](../../features/json_patch.md) ([RFC 6902](https://tools.ietf.org/html/rfc6902)) for that.
[`merge_diff`](merge_diff.md) has a matching limitation, see its notes.
- A [discarded](is_discarded.md) value is treated like any other non-object value: a discarded
`apply_patch` turns the target into a discarded value, and an object patch replaces a discarded target by an object
as described above.
`apply_patch` may be `#!cpp *this` itself or refer to a value contained in `#!cpp *this` (for example, a subobject
returned by `#!cpp (*this)[key]`); it is read as it was when `merge_patch()` was called, before any modification of
`#!cpp *this`.
## Examples
@@ -85,13 +65,11 @@ cost also includes one copy of `apply_patch` (see the notes below).
## See also
- [RFC 7396 (JSON Merge Patch)](https://tools.ietf.org/html/rfc7396) - specification of JSON Merge Patch
- [`patch`](patch.md) - apply a JSON patch
- [`merge_diff`](merge_diff.md) - creates a diff as a JSON Merge Patch
- [JSON Merge Patch](../../features/merge_patch.md) - the article on JSON Merge Patch
- [RFC 7396 (JSON Merge Patch)](https://tools.ietf.org/html/rfc7396)
- [patch](patch.md) apply a JSON patch
## Version history
- Added in version 3.1.0.
- Added in version 3.0.0.
- Fixed use of freed or relocated memory when `apply_patch` is `#!cpp *this` or refers to a value contained in
`#!cpp *this`, in version 3.13.0.
+2 -5
View File
@@ -48,11 +48,8 @@ Constant.
## See also
- [`NLOHMANN_JSON_VERSION_MAJOR`](../macros/nlohmann_json_version_major.md) /
[`NLOHMANN_JSON_VERSION_MINOR`](../macros/nlohmann_json_version_major.md) /
[`NLOHMANN_JSON_VERSION_PATCH`](../macros/nlohmann_json_version_major.md) - library version information
- [Integration](../../integration/index.md) - integrate the library
- [Supported Macros](../../features/macros.md) - guide to all supported macros
- [**NLOHMANN_JSON_VERSION_MAJOR**/**NLOHMANN_JSON_VERSION_MINOR**/**NLOHMANN_JSON_VERSION_PATCH**](../macros/nlohmann_json_version_major.md)
\- library version information
## Version history
Loaded 100 of 1017 files, more files were not shown because too many files have changed in this diff. Show more