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<!doctype html><html lang=en class=no-js> <head><meta charset=utf-8><meta name=viewport content="width=device-width,initial-scale=1"><meta name=author content="Niels Lohmann"><link href="https://json.nlohmann.me/api/basic_json/from_ubjson/" rel="canonical"><link href=../from_msgpack/ rel=prev><link href=../front/ rel=next><link rel=icon href=../../../assets/images/favicon.png><meta name=generator content="mkdocs-1.6.1, mkdocs-material-9.7.7"><title>from_ubjson - JSON for Modern C++</title><link rel=stylesheet href=../../../assets/stylesheets/main.ec1eaa64.min.css><link rel=stylesheet href=../../../assets/stylesheets/palette.ab4e12ef.min.css><link rel="stylesheet" href="../../../assets/external/fonts.googleapis.com/css.61a430c9.css"><style>:root{--md-text-font:"Roboto";--md-code-font:"JetBrains Mono"}</style><link rel=stylesheet href=../../../css/custom.css><script>__md_scope=new 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data-md-component=logo> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M12 8a3 3 0 0 0 3-3 3 3 0 0 0-3-3 3 3 0 0 0-3 3 3 3 0 0 0 3 3m0 3.54C9.64 9.35 6.5 8 3 8v11c3.5 0 6.64 1.35 9 3.54 2.36-2.19 5.5-3.54 9-3.54V8c-3.5 0-6.64 1.35-9 3.54"/></svg> </a> <label class="md-header__button md-icon" for=__drawer> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M3 6h18v2H3zm0 5h18v2H3zm0 5h18v2H3z"/></svg> </label> <div class=md-header__title data-md-component=header-title> <div class=md-header__ellipsis> <div class=md-header__topic> <span class=md-ellipsis> JSON for Modern C++ </span> </div> <div class=md-header__topic data-md-component=header-topic> <span class=md-ellipsis> from_ubjson </span> </div> </div> </div> <form class=md-header__option data-md-component=palette> <input class=md-option data-md-color-media="(prefers-color-scheme: light)" data-md-color-scheme=default data-md-color-primary=indigo data-md-color-accent=indigo aria-label="Switch to dark 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<span class=k>template</span><span class=o>&lt;</span><span class=k>typename</span><span class=w> </span><span class=nc>InputType</span><span class=o>&gt;</span>
<span class=k>static</span><span class=w> </span><span class=n>basic_json</span><span class=w> </span><span class=n>from_ubjson</span><span class=p>(</span><span class=n>InputType</span><span class=o>&amp;&amp;</span><span class=w> </span><span class=n>i</span><span class=p>,</span>
<span class=w> </span><span class=k>const</span><span class=w> </span><span class=kt>bool</span><span class=w> </span><span class=n>strict</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=nb>true</span><span class=p>,</span>
<span class=w> </span><span class=k>const</span><span class=w> </span><span class=kt>bool</span><span class=w> </span><span class=n>allow_exceptions</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=nb>true</span><span class=p>);</span>
<span class=w> </span><span class=k>const</span><span class=w> </span><span class=kt>bool</span><span class=w> </span><span class=n>allow_exceptions</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=nb>true</span><span class=p>,</span>
<span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>error_handler_t</span><span class=w> </span><span class=n>error_handler</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>error_handler_t</span><span class=o>::</span><span class=n>keep</span><span class=p>);</span>
<span class=c1>// (2)</span>
<span class=k>template</span><span class=o>&lt;</span><span class=k>typename</span><span class=w> </span><span class=nc>IteratorType</span><span class=p>,</span><span class=w> </span><span class=k>typename</span><span class=w> </span><span class=nc>SentinelType</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>IteratorType</span><span class=o>&gt;</span>
<span class=k>static</span><span class=w> </span><span class=n>basic_json</span><span class=w> </span><span class=n>from_ubjson</span><span class=p>(</span><span class=n>IteratorType</span><span class=w> </span><span class=n>first</span><span class=p>,</span><span class=w> </span><span class=n>SentinelType</span><span class=w> </span><span class=n>last</span><span class=p>,</span>
<span class=w> </span><span class=k>const</span><span class=w> </span><span class=kt>bool</span><span class=w> </span><span class=n>strict</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=nb>true</span><span class=p>,</span>
<span class=w> </span><span class=k>const</span><span class=w> </span><span class=kt>bool</span><span class=w> </span><span class=n>allow_exceptions</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=nb>true</span><span class=p>);</span>
</code></pre></div> <p>Deserializes a given input to a <abbr title="JavaScript Object Notation">JSON</abbr> value using the <abbr title="Universal Binary JSON">UBJSON</abbr> (Universal Binary <abbr title="JavaScript Object Notation">JSON</abbr>) serialization format.</p> <ol> <li>Reads from a compatible input.</li> <li>Reads from an iterator range, or an iterator and a sentinel of a different type (C++20 ranges support).</li> </ol> <p>The exact mapping and its limitations are described on a <a href=../../../features/binary_formats/ubjson/ >dedicated page</a>.</p> <h2 id=template-parameters>Template parameters<a class=headerlink href=#template-parameters title="Permanent link">&para;</a></h2> <dl> <dt><code>InputType</code></dt> <dd> <p>A compatible input, for instance:</p> <ul> <li>an <code>std::istream</code> object</li> <li>a <code>FILE</code> pointer</li> <li>a C-style array of characters</li> <li>a pointer to a null-terminated string of single byte characters</li> <li>a container <code>obj</code> for which <code>begin(obj)</code> and <code>end(obj)</code> produce a valid pair of iterators (as found via <abbr title="Argument-dependent lookup">ADL</abbr> or member functions, with semantics compatible to <code>std::begin</code> and <code>std::end</code>)</li> </ul> </dd> <dt><code>IteratorType</code></dt> <dd>a compatible iterator type</dd> <dt><code>SentinelType</code></dt> <dd> <p>defaults to <code>IteratorType</code>; may be a different type comparable to <code>IteratorType</code> via <code>operator!=</code>, for instance.</p> <ul> <li>a custom sentinel type for C++20 ranges</li> <li><code>std::default_sentinel_t</code>, when <code>IteratorType</code> is <code>std::counted_iterator</code></li> </ul> </dd> </dl> <h2 id=parameters>Parameters<a class=headerlink href=#parameters title="Permanent link">&para;</a></h2> <dl> <dt><code>i</code> (in)</dt> <dd>an input in <abbr title="Universal Binary JSON">UBJSON</abbr> format convertible to an input adapter</dd> <dt><code>first</code> (in)</dt> <dd>iterator to the start of the input</dd> <dt><code>last</code> (in)</dt> <dd>iterator to the end of the input, or a sentinel value that compares equal to the end iterator with <code>operator!=</code></dd> <dt><code>strict</code> (in)</dt> <dd>whether to expect the input to be consumed until <abbr title="End of File">EOF</abbr> (<code class=highlight><span class=nb>true</span></code> by default)</dd> <dt><code>allow_exceptions</code> (in)</dt> <dd>whether to throw exceptions in case of a parse error (optional, <code class=highlight><span class=nb>true</span></code> by default)</dd> </dl> <h2 id=return-value>Return value<a class=headerlink href=#return-value title="Permanent link">&para;</a></h2> <p>deserialized <abbr title="JavaScript Object Notation">JSON</abbr> value; in case of a parse error and <code>allow_exceptions</code> set to <code class=highlight><span class=nb>false</span></code>, the return value will be <code>value_t::discarded</code>. The latter can be checked with <a href=../is_discarded/ ><code>is_discarded</code></a>.</p> <h2 id=exception-safety>Exception safety<a class=headerlink href=#exception-safety title="Permanent link">&para;</a></h2> <p>Strong guarantee: if an exception is thrown, there are no changes in the <abbr title="JavaScript Object Notation">JSON</abbr> value.</p> <h2 id=exceptions>Exceptions<a class=headerlink href=#exceptions title="Permanent link">&para;</a></h2> <ul> <li>Throws <a href=../../../home/exceptions/#jsonexceptionparse_error110>parse_error.110</a> if the given input ends prematurely or the end of the file was not reached when <code>strict</code> was set to true</li> <li>Throws <a href=../../../home/exceptions/#jsonexceptionparse_error112>parse_error.112</a> if a parse error occurs</li> <li>Throws <a href=../../../home/exceptions/#jsonexceptionparse_error113>parse_error.113</a> if a string could not be parsed successfully</li> <li>Throws <a href=../../../home/exceptions/#jsonexceptionout_of_range408>out_of_range.408</a> if the size of an optimized container or n-dimensional array cannot be represented by <code>std::size_t</code></li> </ul> <h2 id=complexity>Complexity<a class=headerlink href=#complexity title="Permanent link">&para;</a></h2> <p>Linear in the size of the input.</p> <h2 id=examples>Examples<a class=headerlink href=#examples title="Permanent link">&para;</a></h2> <details class=example> <summary>Example</summary> <p>The example shows the deserialization of a byte vector in <abbr title="Universal Binary JSON">UBJSON</abbr> format to a <abbr title="JavaScript Object Notation">JSON</abbr> value.</p> <div class=highlight><pre><span></span><code><span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;iostream&gt;</span>
<span class=w> </span><span class=k>const</span><span class=w> </span><span class=kt>bool</span><span class=w> </span><span class=n>allow_exceptions</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=nb>true</span><span class=p>,</span>
<span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>error_handler_t</span><span class=w> </span><span class=n>error_handler</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>error_handler_t</span><span class=o>::</span><span class=n>keep</span><span class=p>);</span>
</code></pre></div> <p>Deserializes a given input to a <abbr title="JavaScript Object Notation">JSON</abbr> value using the <abbr title="Universal Binary JSON">UBJSON</abbr> (Universal Binary <abbr title="JavaScript Object Notation">JSON</abbr>) serialization format.</p> <ol> <li>Reads from a compatible input.</li> <li>Reads from an iterator range, or an iterator and a sentinel of a different type (C++20 ranges support).</li> </ol> <p>The exact mapping and its limitations are described on a <a href=../../../features/binary_formats/ubjson/ >dedicated page</a>.</p> <h2 id=template-parameters>Template parameters<a class=headerlink href=#template-parameters title="Permanent link">&para;</a></h2> <dl> <dt><code>InputType</code></dt> <dd> <p>A compatible input, for instance:</p> <ul> <li>an <code>std::istream</code> object</li> <li>a <code>FILE</code> pointer</li> <li>a C-style array of characters</li> <li>a pointer to a null-terminated string of single byte characters</li> <li>a container <code>obj</code> for which <code>begin(obj)</code> and <code>end(obj)</code> produce a valid pair of iterators (as found via <abbr title="Argument-dependent lookup">ADL</abbr> or member functions, with semantics compatible to <code>std::begin</code> and <code>std::end</code>)</li> </ul> </dd> <dt><code>IteratorType</code></dt> <dd>a compatible iterator type</dd> <dt><code>SentinelType</code></dt> <dd> <p>defaults to <code>IteratorType</code>; may be a different type comparable to <code>IteratorType</code> via <code>operator!=</code>, for instance.</p> <ul> <li>a custom sentinel type for C++20 ranges</li> <li><code>std::default_sentinel_t</code>, when <code>IteratorType</code> is <code>std::counted_iterator</code></li> </ul> </dd> </dl> <h2 id=parameters>Parameters<a class=headerlink href=#parameters title="Permanent link">&para;</a></h2> <dl> <dt><code>i</code> (in)</dt> <dd>an input in <abbr title="Universal Binary JSON">UBJSON</abbr> format convertible to an input adapter</dd> <dt><code>first</code> (in)</dt> <dd>iterator to the start of the input</dd> <dt><code>last</code> (in)</dt> <dd>iterator to the end of the input, or a sentinel value that compares equal to the end iterator with <code>operator!=</code></dd> <dt><code>strict</code> (in)</dt> <dd>whether to expect the input to be consumed until <abbr title="End of File">EOF</abbr> (<code class=highlight><span class=nb>true</span></code> by default)</dd> <dt><code>allow_exceptions</code> (in)</dt> <dd>whether to throw exceptions in case of a parse error (optional, <code class=highlight><span class=nb>true</span></code> by default)</dd> <dt><code>error_handler</code> (in)</dt> <dd>how to treat a string value or object key that is not valid <abbr title="Unicode Transformation Format">UTF</abbr>-8; see <a href=../error_handler_t/ ><code>error_handler_t</code></a>. <abbr title="Universal Binary JSON">UBJSON</abbr> does not require a decoder to reject ill-formed <abbr title="Unicode Transformation Format">UTF</abbr>-8, so checking is opt-in: the default, <code>keep</code>, does not check at all, as every binary reader did before this parameter was added; <code>strict</code> checks and throws; <code>replace</code>/<code>ignore</code> sanitize the string the same way <a href=../dump/ ><code>dump</code></a> would</dd> </dl> <h2 id=return-value>Return value<a class=headerlink href=#return-value title="Permanent link">&para;</a></h2> <p>deserialized <abbr title="JavaScript Object Notation">JSON</abbr> value; in case of a parse error and <code>allow_exceptions</code> set to <code class=highlight><span class=nb>false</span></code>, the return value will be <code>value_t::discarded</code>. The latter can be checked with <a href=../is_discarded/ ><code>is_discarded</code></a>.</p> <h2 id=exception-safety>Exception safety<a class=headerlink href=#exception-safety title="Permanent link">&para;</a></h2> <p>Strong guarantee: if an exception is thrown, there are no changes in the <abbr title="JavaScript Object Notation">JSON</abbr> value.</p> <h2 id=exceptions>Exceptions<a class=headerlink href=#exceptions title="Permanent link">&para;</a></h2> <ul> <li>Throws <a href=../../../home/exceptions/#jsonexceptionparse_error110>parse_error.110</a> if the given input ends prematurely or the end of the file was not reached when <code>strict</code> was set to true</li> <li>Throws <a href=../../../home/exceptions/#jsonexceptionparse_error112>parse_error.112</a> if a parse error occurs</li> <li>Throws <a href=../../../home/exceptions/#jsonexceptionparse_error113>parse_error.113</a> if a string could not be parsed successfully, or if a string value or object key is not valid <abbr title="Unicode Transformation Format">UTF</abbr>-8 and <code>error_handler</code> is <code>strict</code></li> <li>Throws <a href=../../../home/exceptions/#jsonexceptionout_of_range408>out_of_range.408</a> if the size of an optimized container or n-dimensional array cannot be represented by <code>std::size_t</code></li> </ul> <Line truncated
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;iomanip&gt;</span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
@@ -32,4 +34,4 @@
<span class=w> </span><span class=nt>"compact"</span><span class=p>:</span><span class=w> </span><span class=kc>true</span><span class=p>,</span>
<span class=w> </span><span class=nt>"schema"</span><span class=p>:</span><span class=w> </span><span class=mi>0</span>
<span class=p>}</span>
</code></pre></div> </details> <h2 id=see-also>See also<a class=headerlink href=#see-also title="Permanent link">&para;</a></h2> <ul> <li><a href=../to_ubjson/ >to_ubjson</a> create a <abbr title="Universal Binary JSON">UBJSON</abbr> serialization of a <abbr title="JavaScript Object Notation">JSON</abbr> value</li> <li><a href=../from_cbor/ >from_cbor</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in <abbr title="Concise Binary Object Representation">CBOR</abbr> format</li> <li><a href=../from_msgpack/ >from_msgpack</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in MessagePack format</li> <li><a href=../from_bson/ >from_bson</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in <abbr title="Binary JSON">BSON</abbr> format</li> <li><a href=../from_bjdata/ >from_bjdata</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in <abbr title="Binary JData">BJData</abbr> format</li> <li><a href=../from_bon8/ >from_bon8</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in <abbr title="Binary Object Notation 8">BON8</abbr> format</li> </ul> <h2 id=version-history>Version history<a class=headerlink href=#version-history title="Permanent link">&para;</a></h2> <ul> <li>Added in version 3.1.0.</li> <li>Added <code>allow_exceptions</code> parameter in version 3.2.0.</li> <li>Extended container support (1) to include types with lvalue-only <abbr title="Argument-dependent lookup">ADL</abbr> <code>begin</code>/<code>end</code> (matching <code>std::begin</code>/<code>std::end</code> semantics) in version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>.</li> <li>Extended overload (2) to accept heterogeneous iterator+sentinel pairs (C++20 ranges support) in version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>.</li> </ul> <div class="admonition warning"> <p class=admonition-title>Deprecation</p> <ul> <li>Overload (2) replaces calls to <code>from_ubjson</code> with a pointer and a length as first two parameters, which has been deprecated in version 3.8.0. This overload will be removed in version 4.0.0. Please replace all calls like <code class=highlight><span class=n>from_ubjson</span><span class=p>(</span><span class=n>ptr</span><span class=p>,</span><span class=w> </span><span class=n>len</span><span class=p>,</span><span class=w> </span><span class=p>...);</span></code> with <code class=highlight><span class=n>from_ubjson</span><span class=p>(</span><span class=n>ptr</span><span class=p>,</span><span class=w> </span><span class=n>ptr</span><span class=o>+</span><span class=n>len</span><span class=p>,</span><span class=w> </span><span class=p>...);</span></code>.</li> <li>Overload (2) replaces calls to <code>from_ubjson</code> with a pair of iterators as their first parameter, which has been deprecated in version 3.8.0. This overload will be removed in version 4.0.0. Please replace all calls like <code class=highlight><span class=n>from_ubjson</span><span class=p>({</span><span class=n>ptr</span><span class=p>,</span><span class=w> </span><span class=n>ptr</span><span class=o>+</span><span class=n>len</span><span class=p>},</span><span class=w> </span><span class=p>...);</span></code> with <code class=highlight><span class=n>from_ubjson</span><span class=p>(</span><span class=n>ptr</span><span class=p>,</span><span class=w> </span><span class=n>ptr</span><span class=o>+</span><span class=n>len</span><span class=p>,</span><span class=w> </span><span class=p>...);</span></code>.</li> </ul> <p>You should be warned by your compiler with a <code>-Wdeprecated-declarations</code> warning if you are using a deprecated function.</p> <p>See the <a href=../../../integration/migration_guide/#parsing>migration guide</a> for how to update existing code.</p> </div> <!-- https://squidfunk.github.io/mkdocs-material/reference/tooltips/#adding-a-glossary --> <aside class=md-source-file> <span class=md-source-file__fact> <span class=md-icon title="Last update"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M21 13.1c-.1 0-.3.1-.4.2l-1 1 2.1 2.1 1-1c.2-.2.2-.6 0-.8l-1.3-1.3c-.1-.1-.2-.2-.4-.2m-1.9 1.8-6.1 6V23h2.1l6.1-6.1zM12.5 7v5.2l4 2.4-1 1L11 13V7zM11 21.9c-5.1-.5-9-4.8-9-9.9C2 6.5 6.5 2 12 2c5.3 0 9.6 4.1 10 9.3-.3-.1-.6-.2-1-.2s-.7.1-1 .2C19.6 7.2 16.2 4 12 4c-4.4 0-8 3.6-8 8 0 4.1 3.1 7.5 7.1 7.9l-.1.2z"/></svg> </span> <span class="git-revision-date-localized-plugin git-revision-date-localized-plugin-date" title="October 2, 2026 09:32:15 UTC">October 2, 2026</span> </span> </aside> </article> </div> <script>var tabs=__md_get("__tabs");if(Array.isArray(tabs))e:for(var set of document.querySelectorAll(".tabbed-set")){var labels=set.querySelector(".tabbed-labels");for(var tab of tabs)for(var label oLine truncated
</code></pre></div> </details> <h2 id=see-also>See also<a class=headerlink href=#see-also title="Permanent link">&para;</a></h2> <ul> <li><a href=../to_ubjson/ >to_ubjson</a> create a <abbr title="Universal Binary JSON">UBJSON</abbr> serialization of a <abbr title="JavaScript Object Notation">JSON</abbr> value</li> <li><a href=../from_cbor/ >from_cbor</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in <abbr title="Concise Binary Object Representation">CBOR</abbr> format</li> <li><a href=../from_msgpack/ >from_msgpack</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in MessagePack format</li> <li><a href=../from_bson/ >from_bson</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in <abbr title="Binary JSON">BSON</abbr> format</li> <li><a href=../from_bjdata/ >from_bjdata</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in <abbr title="Binary JData">BJData</abbr> format</li> <li><a href=../from_bon8/ >from_bon8</a> create a <abbr title="JavaScript Object Notation">JSON</abbr> value from an input in <abbr title="Binary Object Notation 8">BON8</abbr> format</li> </ul> <h2 id=version-history>Version history<a class=headerlink href=#version-history title="Permanent link">&para;</a></h2> <ul> <li>Added in version 3.1.0.</li> <li>Added <code>allow_exceptions</code> parameter in version 3.2.0.</li> <li>Extended container support (1) to include types with lvalue-only <abbr title="Argument-dependent lookup">ADL</abbr> <code>begin</code>/<code>end</code> (matching <code>std::begin</code>/<code>std::end</code> semantics) in version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>.</li> <li>Extended overload (2) to accept heterogeneous iterator+sentinel pairs (C++20 ranges support) in version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>.</li> <li>Added <code>error_handler</code> parameter in version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>.</li> </ul> <div class="admonition warning"> <p class=admonition-title>Deprecation</p> <ul> <li>Overload (2) replaces calls to <code>from_ubjson</code> with a pointer and a length as first two parameters, which has been deprecated in version 3.8.0. This overload will be removed in version 4.0.0. Please replace all calls like <code class=highlight><span class=n>from_ubjson</span><span class=p>(</span><span class=n>ptr</span><span class=p>,</span><span class=w> </span><span class=n>len</span><span class=p>,</span><span class=w> </span><span class=p>...);</span></code> with <code class=highlight><span class=n>from_ubjson</span><span class=p>(</span><span class=n>ptr</span><span class=p>,</span><span class=w> </span><span class=n>ptr</span><span class=o>+</span><span class=n>len</span><span class=p>,</span><span class=w> </span><span class=p>...);</span></code>.</li> <li>Overload (2) replaces calls to <code>from_ubjson</code> with a pair of iterators as their first parameter, which has been deprecated in version 3.8.0. This overload will be removed in version 4.0.0. Please replace all calls like <code class=highlight><span class=n>from_ubjson</span><span class=p>({</span><span class=n>ptr</span><span class=p>,</span><span class=w> </span><span class=n>ptr</span><span class=o>+</span><span class=n>len</span><span class=p>},</span><span class=w> </span><span class=p>...);</span></code> with <code class=highlight><span class=n>from_ubjson</span><span class=p>(</span><span class=n>ptr</span><span class=p>,</span><span class=w> </span><span class=n>ptr</span><span class=o>+</span><span class=n>len</span><span class=p>,</span><span class=w> </span><span class=p>...);</span></code>.</li> </ul> <p>You should be warned by your compiler with a <code>-Wdeprecated-declarations</code> warning if you are using a deprecated function.</p> <p>See the <a href=../../../integration/migration_guide/#parsing>migration guide</a> for how to update existing code.</p> </div> <!-- https://squidfunk.github.io/mkdocs-material/reference/tooltips/#adding-a-glossary --> <aside class=md-source-file> <span class=md-source-file__fact> <span class=md-icon title="Last update"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M21 13.1c-.1 0-.3.1-.4.2l-1 1 2.1 2.1 1-1c.2-.2.2-.6 0-.8l-1.3-1.3c-.1-.1-.2-.2-.4-.2m-1.9 1.8-6.1 6V23h2.1l6.1-6.1zM12.5 7v5.2l4 2.4-1 1L11 13V7zM11 21.9c-5.1-.5-9-4.8-9-9.9C2 6.5 6.5 2 12 2c5.3 0 9.6 4.1 10 9.3-.3-.1-.6-.2-1-.2s-.7.1-1 .2C19.6 7.2 16.2 4 12 4c-4.4 0-8 3.6-8 8 0 4.1 3.1 7.5 7.1 7.9l-.1.2z"/></svg> </span> <span class="git-revision-date-localized-plugin git-revision-date-localized-plugin-date" title="October 4, 2026 10:13:49 UTC">October 4, 2026</span> </span> </aside> </article> </div> <script>var tabLine truncated
+8 -3
View File
@@ -5,12 +5,14 @@
template<typename InputType>
static basic_json from_ubjson(InputType&& i,
const bool strict = true,
const bool allow_exceptions = true);
const bool allow_exceptions = true,
const error_handler_t error_handler = error_handler_t::keep);
// (2)
template<typename IteratorType, typename SentinelType = IteratorType>
static basic_json from_ubjson(IteratorType first, SentinelType last,
const bool strict = true,
const bool allow_exceptions = true);
const bool allow_exceptions = true,
const error_handler_t error_handler = error_handler_t::keep);
```
Deserializes a given input to a JSON value using the UBJSON (Universal Binary JSON) serialization format.
@@ -54,6 +56,8 @@ The exact mapping and its limitations are described on a [dedicated page](https:
`allow_exceptions` (in) : whether to throw exceptions in case of a parse error (optional, `true` by default)
`error_handler` (in) : how to treat a string value or object key that is not valid UTF-8; see [`error_handler_t`](https://json.nlohmann.me/api/basic_json/error_handler_t/index.md). UBJSON does not require a decoder to reject ill-formed UTF-8, so checking is opt-in: the default, `keep`, does not check at all, as every binary reader did before this parameter was added; `strict` checks and throws; `replace`/`ignore` sanitize the string the same way [`dump`](https://json.nlohmann.me/api/basic_json/dump/index.md) would
## Return value
deserialized JSON value; in case of a parse error and `allow_exceptions` set to `false`, the return value will be `value_t::discarded`. The latter can be checked with [`is_discarded`](https://json.nlohmann.me/api/basic_json/is_discarded/index.md).
@@ -66,7 +70,7 @@ Strong guarantee: if an exception is thrown, there are no changes in the JSON va
- Throws [parse_error.110](https://json.nlohmann.me/home/exceptions/#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](https://json.nlohmann.me/home/exceptions/#jsonexceptionparse_error112) if a parse error occurs
- Throws [parse_error.113](https://json.nlohmann.me/home/exceptions/#jsonexceptionparse_error113) if a string could not be parsed successfully
- Throws [parse_error.113](https://json.nlohmann.me/home/exceptions/#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 [out_of_range.408](https://json.nlohmann.me/home/exceptions/#jsonexceptionout_of_range408) if the size of an optimized container or n-dimensional array cannot be represented by `std::size_t`
## Complexity
@@ -126,6 +130,7 @@ Output:
- Added `allow_exceptions` parameter in version 3.2.0.
- Extended container support (1) to include types with lvalue-only ADL `begin`/`end` (matching `std::begin`/`std::end` semantics) in version 3.13.0 unreleased.
- Extended overload (2) to accept heterogeneous iterator+sentinel pairs (C++20 ranges support) in version 3.13.0 unreleased.
- Added `error_handler` parameter in version 3.13.0 unreleased.
Deprecation