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+# <small>nlohmann::basic_json_view::</small>dump
+
+```cpp
+string_t dump(const int indent = -1,
+              const char indent_char = ' ',
+              const bool ensure_ascii = false,
+              const number_format numbers = number_format::shortest) const;
+```
+
+Serializes this value (and its subtree) directly from the flat index, without ever building a `BasicJsonType` value
+first. With the default `#!cpp numbers == number_format::shortest`, the result is the same string
+[`BasicJsonType::dump`](../basic_json/dump.md) would produce for the value
+[`BasicJsonType::parse()`](../basic_json/parse.md) builds from the same source text, called with the same `indent`,
+`indent_char`, and `ensure_ascii` -- except that members of an object appear in document order rather than sorted by
+key, and *every* occurrence of a repeated key is written rather than only the last one (see
+[Notes on duplicate keys](operator[].md#notes)). For a `json_view` (whose `BasicJsonType` is not ordered), this means
+`dump()` can print an object's members in a different order than [`materialize()`](materialize.md)`.dump()` of the
+same subtree.
+
+## Parameters
+
+`indent` (in)
+:   If `indent` is nonnegative, array elements and object members are pretty-printed with that indent level. An
+    indent level of `0` only inserts newlines. `-1` (the default) selects the most compact representation.
+
+`indent_char` (in)
+:   The character used for indentation if `indent` is greater than `0`. The default is ` ` (space).
+
+`ensure_ascii` (in)
+:   If `ensure_ascii` is `#!cpp true`, all non-ASCII characters in the output are escaped with `\uXXXX` sequences, and
+    the result consists of ASCII characters only.
+
+`numbers` (in)
+:   how to write numbers, see [`number_format`](number_format.md): `shortest` (the default) writes them the way
+    [`BasicJsonType::dump`](../basic_json/dump.md) would; `source` copies every number exactly as it appears in the
+    source text.
+
+## Return value
+
+string containing the serialization of this value, or `#!cpp "<discarded>"` if the view is
+[discarded](is_discarded.md).
+
+## Exception safety
+
+Strong exception safety: if an exception is thrown, there are no changes to the view or the document it refers to.
+
+## Exceptions
+
+May throw `#!cpp std::bad_alloc` if allocating the output string fails. Unlike
+[`BasicJsonType::dump`](../basic_json/dump.md), there is no `error_handler` parameter and no
+[`type_error.316`](../../home/exceptions.md#jsonexceptiontype_error316): the view only ever holds text the parser
+already validated as UTF-8, so there is nothing to replace or ignore.
+
+## Complexity
+
+Linear in the size of the output text.
+
+## Notes
+
+The walk over the subtree is iterative, so the nesting depth it can write is limited by available memory only, not by
+the call stack -- as for [`materialize()`](materialize.md).
+
+Strings are escaped by the same rules as [`BasicJsonType::dump`](../basic_json/dump.md).
+
+With `#!cpp numbers == number_format::shortest`, floats are written with the library's shortest round-trip conversion,
+exactly as [`BasicJsonType::dump`](../basic_json/dump.md) would (e.g. `#!cpp 1.5`, `#!cpp 100.0`, `#!cpp 1e+100`), and
+integers are copied from the source text -- already canonical in JSON, so this matches their shortest form too --
+except that `#!cpp -0` is written as `#!cpp 0`, the way [`BasicJsonType::parse()`](../basic_json/parse.md) reads it.
+
+`#!cpp number_format::source` copies every number exactly as written in the source text instead, with no exception
+for `#!cpp -0` -- `#!cpp 1.50`, `#!cpp 1E2`, `#!cpp -0.0`, `#!cpp -0`, or all digits of an integer literal with more
+digits than any number type holds (such a literal is itself classified as a float, see
+[What is different](../../features/json_view.md#what-is-different)) -- something `BasicJsonType` cannot do, since
+parsing already reduces every number to its parsed value.
+
+## Examples
+
+??? example
+
+    The example below forwards a single record out of a larger batch, and re-serializes a configuration file, both
+    without ever building a `BasicJsonType` value for the surrounding array or for the parts of it that were not
+    needed. It also shows that [`materialize()`](materialize.md)`.dump()` of the configuration sorts its keys, where
+    `dump()` on the view keeps the order they appear in the source text.
+
+    ```cpp
+    #include <iostream>
+    #include <nlohmann/json_view.hpp>
+    
+    using json_document = nlohmann::json_document;
+    using json_view = nlohmann::json_view;
+    
+    int main()
+    {
+        // a large batch of sensor readings -- forward just the one that changed,
+        // without ever building a basic_json value for the batch or for the
+        // readings that are not needed
+        const json_document batch = json_document::parse(R"(
+          [{"id": 1, "temp": 21.5}, {"id": 2, "temp": 87.3}, {"id": 3, "temp": 21.7}]
+        )");
+        const json_view readings = batch.root();
+        std::cout << readings[1].dump() << '\n';
+    
+        // a configuration file -- dump() on the view keeps the member order of
+        // the source text; a json value's object_t is std::map, so
+        // materialize().dump() of the very same view sorts the keys instead
+        const json_document config = json_document::parse(
+                                         R"({"name": "cache", "host": "db1", "port": 6379, "timeout": 30})");
+        std::cout << config.root().dump(2) << "\n\n";
+        std::cout << config.root().materialize().dump(2) << '\n';
+    }
+    
+    ```
+
+    Output:
+
+    ```json
+    {"id":2,"temp":87.3}
+    {
+      "name": "cache",
+      "host": "db1",
+      "port": 6379,
+      "timeout": 30
+    }
+    
+    {
+      "host": "db1",
+      "name": "cache",
+      "port": 6379,
+      "timeout": 30
+    }
+    
+    ```
+
+## See also
+
+- [`number_format`](number_format.md) - how `dump()` writes numbers
+- [operator<<](operator_ltlt.md) - serialize this value to a stream
+- [materialize](materialize.md) - build a `BasicJsonType` value, e.g. to use `BasicJsonType::dump`'s `error_handler`
+- [`BasicJsonType::dump`](../basic_json/dump.md) - the corresponding function of `basic_json`
+
+## Version history
+
+- Added in version 3.13.0.