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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/home/exceptions/ rel=canonical><link href=../faq/ rel=prev><link href=../releases/ rel=next><link rel=icon href=../../assets/images/favicon.png><meta name=generator content="mkdocs-1.5.3, mkdocs-material-9.4.7"><title>Exceptions - JSON for Modern C++</title><link rel=stylesheet href=../../assets/stylesheets/main.4b4a2bd9.min.css><link rel=stylesheet href=../../assets/stylesheets/palette.356b1318.min.css><link rel=preconnect href=https://fonts.gstatic.com crossorigin><link rel=stylesheet href="https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,700,700i%7CJetBrains+Mono:400,400i,700,700i&display=fallback"><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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<span class=cp>#define JSON_TRY_USER if(true)</span>
<span class=cp>#define JSON_CATCH_USER(exception) if(false)</span>
@@ -8,76 +8,76 @@
<span class=cp> &lt;&lt; (exception).what() &lt;&lt; std::endl; \</span>
<span class=cp> std::abort();}</span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span><span class=cp></span>
</code></pre></div> </details> <p>Note the explanatory <a href=https://en.cppreference.com/w/cpp/error/exception/what><code>what()</code></a> string of exceptions is not available for MSVC if exceptions are disabled, see <a href=https://github.com/nlohmann/json/discussions/2824>#2824</a>.</p> <p>See <a href=../../api/macros/json_throw_user/ >documentation of <code>JSON_TRY_USER</code>, <code>JSON_CATCH_USER</code> and <code>JSON_THROW_USER</code></a> for more information.</p> <h3 id=extended-diagnostic-messages>Extended diagnostic messages<a class=headerlink href=#extended-diagnostic-messages title="Permanent link">&para;</a></h3> <p>Exceptions in the library are thrown in the local context of the JSON value they are detected. This makes detailed diagnostics messages, and hence debugging, difficult.</p> <details class=example> <summary>Example</summary> <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=cp></span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span><span class=cp></span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
</code></pre></div> </details> <p>Note the explanatory <a href=https://en.cppreference.com/w/cpp/error/exception/what><code>what()</code></a> string of exceptions is not available for MSVC if exceptions are disabled, see <a href=https://github.com/nlohmann/json/discussions/2824>#2824</a>.</p> <p>See <a href=../../api/macros/json_throw_user/ >documentation of <code>JSON_TRY_USER</code>, <code>JSON_CATCH_USER</code> and <code>JSON_THROW_USER</code></a> for more information.</p> <h3 id=extended-diagnostic-messages>Extended diagnostic messages<a class=headerlink href=#extended-diagnostic-messages title="Permanent link">&para;</a></h3> <p>Exceptions in the library are thrown in the local context of the JSON value they are detected. This makes detailed diagnostics messages, and hence debugging, difficult.</p> <details class=example> <summary>Example</summary> <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=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span><span class=w></span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span><span class=w></span>
<span class=p>{</span><span class=w></span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;street&quot;</span><span class=p>]</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;Fake Street&quot;</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;housenumber&quot;</span><span class=p>]</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;12&quot;</span><span class=p>;</span><span class=w></span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span>
<span class=p>{</span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=p>;</span>
<span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;street&quot;</span><span class=p>]</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;Fake Street&quot;</span><span class=p>;</span>
<span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;housenumber&quot;</span><span class=p>]</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;12&quot;</span><span class=p>;</span>
<span class=w> </span><span class=k>try</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=w> </span><span class=kt>int</span><span class=w> </span><span class=n>housenumber</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;housenumber&quot;</span><span class=p>];</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>exception</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>try</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=kt>int</span><span class=w> </span><span class=n>housenumber</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;housenumber&quot;</span><span class=p>];</span>
<span class=w> </span><span class=p>}</span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>exception</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=p>;</span>
<span class=w> </span><span class=p>}</span>
<span class=p>}</span>
</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.302] type must be number, but is string
</code></pre></div> <p>This exception can be hard to debug if storing the value <code class=highlight><span class=s>&quot;12&quot;</span><span class=w></span></code> and accessing it is further apart.</p> </details> <p>To create better diagnostics messages, each JSON value needs a pointer to its parent value such that a global context (i.e., a path from the root value to the value that lead to the exception) can be created. That global context is provided as <a href=../../features/json_pointer/ >JSON Pointer</a>.</p> <p>As this global context comes at the price of storing one additional pointer per JSON value and runtime overhead to maintain the parent relation, extended diagnostics are disabled by default. They can, however, be enabled by defining the preprocessor symbol <a href=../../api/macros/json_diagnostics/ ><code>JSON_DIAGNOSTICS</code></a> to <code>1</code> before including <code>json.hpp</code>.</p> <details class=example> <summary>Example</summary> <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=cp></span>
</code></pre></div> <p>This exception can be hard to debug if storing the value <code class=highlight><span class=s>&quot;12&quot;</span></code> and accessing it is further apart.</p> </details> <p>To create better diagnostics messages, each JSON value needs a pointer to its parent value such that a global context (i.e., a path from the root value to the value that lead to the exception) can be created. That global context is provided as <a href=../../features/json_pointer/ >JSON Pointer</a>.</p> <p>As this global context comes at the price of storing one additional pointer per JSON value and runtime overhead to maintain the parent relation, extended diagnostics are disabled by default. They can, however, be enabled by defining the preprocessor symbol <a href=../../api/macros/json_diagnostics/ ><code>JSON_DIAGNOSTICS</code></a> to <code>1</code> before including <code>json.hpp</code>.</p> <details class=example> <summary>Example</summary> <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=cp># define JSON_DIAGNOSTICS 1</span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span><span class=cp></span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span><span class=w></span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span><span class=w></span>
<span class=p>{</span><span class=w></span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;street&quot;</span><span class=p>]</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;Fake Street&quot;</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;housenumber&quot;</span><span class=p>]</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;12&quot;</span><span class=p>;</span><span class=w></span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span>
<span class=p>{</span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=p>;</span>
<span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;street&quot;</span><span class=p>]</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;Fake Street&quot;</span><span class=p>;</span>
<span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;housenumber&quot;</span><span class=p>]</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;12&quot;</span><span class=p>;</span>
<span class=w> </span><span class=k>try</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=w> </span><span class=kt>int</span><span class=w> </span><span class=n>housenumber</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;housenumber&quot;</span><span class=p>];</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>exception</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>try</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=kt>int</span><span class=w> </span><span class=n>housenumber</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>j</span><span class=p>[</span><span class=s>&quot;address&quot;</span><span class=p>][</span><span class=s>&quot;housenumber&quot;</span><span class=p>];</span>
<span class=w> </span><span class=p>}</span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>exception</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=p>;</span>
<span class=w> </span><span class=p>}</span>
<span class=p>}</span>
</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.302] (/address/housenumber) type must be number, but is string
</code></pre></div> <p>Now the exception message contains a JSON Pointer <code>/address/housenumber</code> that indicates which value has the wrong type.</p> </details> <p>See <a href=../../api/macros/json_diagnostics/ >documentation of <code>JSON_DIAGNOSTICS</code></a> for more information.</p> <h2 id=parse-errors>Parse errors<a class=headerlink href=#parse-errors title="Permanent link">&para;</a></h2> <p>This exception is thrown by the library when a parse error occurs. Parse errors can occur during the deserialization of JSON text, CBOR, MessagePack, as well as when using JSON Patch.</p> <p>Exceptions have ids 1xx.</p> <div class="admonition info"> <p class=admonition-title>Byte index</p> <p>Member <code>byte</code> holds the byte index of the last read character in the input file.</p> <p>For an input with n bytes, 1 is the index of the first character and n+1 is the index of the terminating null byte or the end of file. This also holds true when reading a byte vector (CBOR or MessagePack).</p> </div> <details class=example> <summary>Example</summary> <p>The following code shows how a <code>parse_error</code> exception can be caught.</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=cp></span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span><span class=cp></span>
</code></pre></div> <p>Now the exception message contains a JSON Pointer <code>/address/housenumber</code> that indicates which value has the wrong type.</p> </details> <p>See <a href=../../api/macros/json_diagnostics/ >documentation of <code>JSON_DIAGNOSTICS</code></a> for more information.</p> <h2 id=parse-errors>Parse errors<a class=headerlink href=#parse-errors title="Permanent link">&para;</a></h2> <p>This exception is thrown by the library when a parse error occurs. Parse errors can occur during the deserialization of JSON text, CBOR, MessagePack, as well as when using JSON Patch.</p> <p>Exceptions have ids 1xx.</p> <div class="admonition info"> <p class=admonition-title>Byte index</p> <p>Member <code>byte</code> holds the byte index of the last read character in the input file.</p> <p>For an input with n bytes, 1 is the index of the first character and n+1 is the index of the terminating null byte or the end of file. This also holds true when reading a byte vector (CBOR or MessagePack).</p> </div> <details class=example> <summary>Example</summary> <p>The following code shows how a <code>parse_error</code> exception can be caught.</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=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span><span class=w></span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span><span class=w></span>
<span class=p>{</span><span class=w></span>
<span class=w> </span><span class=k>try</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span>
<span class=p>{</span>
<span class=w> </span><span class=k>try</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// parsing input with a syntax error</span>
<span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=s>&quot;[1,2,3,]&quot;</span><span class=p>);</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>parse_error</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=s>&quot;[1,2,3,]&quot;</span><span class=p>);</span>
<span class=w> </span><span class=p>}</span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>parse_error</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// output exception information</span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=w></span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=w></span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;byte position of error: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>byte</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=p>}</span><span class=w></span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;byte position of error: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>byte</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span>
<span class=w> </span><span class=p>}</span>
<span class=p>}</span>
</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>message: [json.exception.parse_error.101] parse error at line 1, column 8: syntax error while parsing value - unexpected &#39;]&#39;; expected &#39;[&#39;, &#39;{&#39;, or a literal
exception id: 101
byte position of error: 8
</code></pre></div> </details> <h3 id=jsonexceptionparse_error101>json.exception.parse_error.101<a class=headerlink href=#jsonexceptionparse_error101 title="Permanent link">&para;</a></h3> <p>This error indicates a syntax error while deserializing a JSON text. The error message describes that an unexpected token (character) was encountered, and the member <code>byte</code> indicates the error position.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p>Input ended prematurely:</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.101] parse error at 2: unexpected end of input; expected string literal
</code></pre></div> <p>No input:</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.101] parse error at line 1, column 1: syntax error while parsing value - unexpected end of input; expected &#39;[&#39;, &#39;{&#39;, or a literal
</code></pre></div> <p>No input:</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.101] parse error at line 1, column 1: attempting to parse an empty input; check that your input string or stream contains the expected JSON
</code></pre></div> <p>Control character was not escaped:</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.101] parse error at line 1, column 2: syntax error while parsing value - invalid string: control character U+0009 (HT) must be escaped to \u0009 or \\; last read: &#39;&quot;&lt;U+0009&gt;&#39;&quot;
</code></pre></div> <p>String was not closed:</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.101] parse error at line 1, column 2: syntax error while parsing value - invalid string: missing closing quote; last read: &#39;&quot;&#39;
</code></pre></div> <p>Invalid number format:</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.101] parse error at line 1, column 3: syntax error while parsing value - invalid number; expected &#39;+&#39;, &#39;-&#39;, or digit after exponent; last read: &#39;1E&#39;
@@ -108,27 +108,27 @@ byte position of error: 8
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.parse_error.113] parse error at byte 2: syntax error while parsing UBJSON char: byte after &#39;C&#39; must be in range 0x00..0x7F; last byte: 0x82
</code></pre></div></p> </div> <h3 id=jsonexceptionparse_error114>json.exception.parse_error.114<a class=headerlink href=#jsonexceptionparse_error114 title="Permanent link">&para;</a></h3> <p>The parsing of the corresponding BSON record type is not implemented (yet).</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.114] parse error at byte 5: Unsupported BSON record type 0xFF
</code></pre></div> </div> <h3 id=jsonexceptionparse_error115>json.exception.parse_error.115<a class=headerlink href=#jsonexceptionparse_error115 title="Permanent link">&para;</a></h3> <p>A UBJSON high-precision number could not be parsed.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.115] parse error at byte 5: syntax error while parsing UBJSON high-precision number: invalid number text: 1A
</code></pre></div> </div> <h2 id=iterator-errors>Iterator errors<a class=headerlink href=#iterator-errors title="Permanent link">&para;</a></h2> <p>This exception is thrown if iterators passed to a library function do not match the expected semantics.</p> <p>Exceptions have ids 2xx.</p> <details class=example> <summary>Example</summary> <p>The following code shows how an <code>invalid_iterator</code> exception can be caught.</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=cp></span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span><span class=cp></span>
</code></pre></div> </div> <h2 id=iterator-errors>Iterator errors<a class=headerlink href=#iterator-errors title="Permanent link">&para;</a></h2> <p>This exception is thrown if iterators passed to a library function do not match the expected semantics.</p> <p>Exceptions have ids 2xx.</p> <details class=example> <summary>Example</summary> <p>The following code shows how an <code>invalid_iterator</code> exception can be caught.</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=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span><span class=w></span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span><span class=w></span>
<span class=p>{</span><span class=w></span>
<span class=w> </span><span class=k>try</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span>
<span class=p>{</span>
<span class=w> </span><span class=k>try</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// calling iterator::key() on non-object iterator</span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;string&quot;</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>iterator</span><span class=w> </span><span class=n>it</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>j</span><span class=p>.</span><span class=n>begin</span><span class=p>();</span><span class=w></span>
<span class=w> </span><span class=k>auto</span><span class=w> </span><span class=n>k</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>it</span><span class=p>.</span><span class=n>key</span><span class=p>();</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>invalid_iterator</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;string&quot;</span><span class=p>;</span>
<span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>iterator</span><span class=w> </span><span class=n>it</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>j</span><span class=p>.</span><span class=n>begin</span><span class=p>();</span>
<span class=w> </span><span class=k>auto</span><span class=w> </span><span class=n>k</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>it</span><span class=p>.</span><span class=n>key</span><span class=p>();</span>
<span class=w> </span><span class=p>}</span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>invalid_iterator</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// output exception information</span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=w></span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=p>}</span><span class=w></span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span>
<span class=w> </span><span class=p>}</span>
<span class=p>}</span>
</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>message: [json.exception.invalid_iterator.207] cannot use key() for non-object iterators
exception id: 207
</code></pre></div> </details> <h3 id=jsonexceptioninvalid_iterator201>json.exception.invalid_iterator.201<a class=headerlink href=#jsonexceptioninvalid_iterator201 title="Permanent link">&para;</a></h3> <p>The iterators passed to constructor <code>basic_json(InputIT first, InputIT last)</code> are not compatible, meaning they do not belong to the same container. Therefore, the range (<code>first</code>, <code>last</code>) is invalid.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.invalid_iterator.201] iterators are not compatible
@@ -146,26 +146,26 @@ exception id: 207
</code></pre></div> </div> <h3 id=jsonexceptioninvalid_iterator212>json.exception.invalid_iterator.212<a class=headerlink href=#jsonexceptioninvalid_iterator212 title="Permanent link">&para;</a></h3> <p>When two iterators are compared, they must belong to the same container.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.invalid_iterator.212] cannot compare iterators of different containers
</code></pre></div> </div> <h3 id=jsonexceptioninvalid_iterator213>json.exception.invalid_iterator.213<a class=headerlink href=#jsonexceptioninvalid_iterator213 title="Permanent link">&para;</a></h3> <p>The order of object iterators cannot be compared, because JSON objects are unordered.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.invalid_iterator.213] cannot compare order of object iterators
</code></pre></div> </div> <h3 id=jsonexceptioninvalid_iterator214>json.exception.invalid_iterator.214<a class=headerlink href=#jsonexceptioninvalid_iterator214 title="Permanent link">&para;</a></h3> <p>Cannot get value for iterator: Either the iterator belongs to a null value or it is an iterator to a primitive type (number, boolean, or string), but the iterator is different to <code>begin()</code>.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.invalid_iterator.214] cannot get value
</code></pre></div> </div> <h2 id=type-errors>Type errors<a class=headerlink href=#type-errors title="Permanent link">&para;</a></h2> <p>This exception is thrown in case of a type error; that is, a library function is executed on a JSON value whose type does not match the expected semantics.</p> <p>Exceptions have ids 3xx.</p> <details class=example> <summary>Example</summary> <p>The following code shows how a <code>type_error</code> exception can be caught.</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=cp></span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span><span class=cp></span>
</code></pre></div> </div> <h2 id=type-errors>Type errors<a class=headerlink href=#type-errors title="Permanent link">&para;</a></h2> <p>This exception is thrown in case of a type error; that is, a library function is executed on a JSON value whose type does not match the expected semantics.</p> <p>Exceptions have ids 3xx.</p> <details class=example> <summary>Example</summary> <p>The following code shows how a <code>type_error</code> exception can be caught.</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=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span><span class=w></span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span><span class=w></span>
<span class=p>{</span><span class=w></span>
<span class=w> </span><span class=k>try</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span>
<span class=p>{</span>
<span class=w> </span><span class=k>try</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// calling push_back() on a string value</span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;string&quot;</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=n>j</span><span class=p>.</span><span class=n>push_back</span><span class=p>(</span><span class=s>&quot;another string&quot;</span><span class=p>);</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>type_error</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=s>&quot;string&quot;</span><span class=p>;</span>
<span class=w> </span><span class=n>j</span><span class=p>.</span><span class=n>push_back</span><span class=p>(</span><span class=s>&quot;another string&quot;</span><span class=p>);</span>
<span class=w> </span><span class=p>}</span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>type_error</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// output exception information</span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=w></span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=p>}</span><span class=w></span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span>
<span class=w> </span><span class=p>}</span>
<span class=p>}</span>
</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>message: [json.exception.type_error.308] cannot use push_back() with string
exception id: 308
</code></pre></div> </details> <h3 id=jsonexceptiontype_error301>json.exception.type_error.301<a class=headerlink href=#jsonexceptiontype_error301 title="Permanent link">&para;</a></h3> <p>To create an object from an initializer list, the initializer list must consist only of a list of pairs whose first element is a string. When this constraint is violated, an array is created instead.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.301] cannot create object from initializer list
@@ -187,31 +187,31 @@ exception id: 308
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.type_error.311] cannot use emplace_back() with number
</code></pre></div></p> </div> <h3 id=jsonexceptiontype_error312>json.exception.type_error.312<a class=headerlink href=#jsonexceptiontype_error312 title="Permanent link">&para;</a></h3> <p>The <code>update()</code> member functions can only be executed for certain JSON types.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.312] cannot use update() with array
</code></pre></div> </div> <h3 id=jsonexceptiontype_error313>json.exception.type_error.313<a class=headerlink href=#jsonexceptiontype_error313 title="Permanent link">&para;</a></h3> <p>The <code>unflatten</code> function converts an object whose keys are JSON Pointers back into an arbitrary nested JSON value. The JSON Pointers must not overlap, because then the resulting value would not be well-defined.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.313] invalid value to unflatten
</code></pre></div> </div> <h3 id=jsonexceptiontype_error314>json.exception.type_error.314<a class=headerlink href=#jsonexceptiontype_error314 title="Permanent link">&para;</a></h3> <p>The <code>unflatten</code> function only works for an object whose keys are JSON Pointers.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p>Calling <code>unflatten()</code> on an array <code class=highlight><span class=p>[</span><span class=mi>1</span><span class=p>,</span><span class=mi>2</span><span class=p>,</span><span class=mi>3</span><span class=p>]</span><span class=w></span></code>:</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.314] only objects can be unflattened
</code></pre></div> </div> <h3 id=jsonexceptiontype_error315>json.exception.type_error.315<a class=headerlink href=#jsonexceptiontype_error315 title="Permanent link">&para;</a></h3> <p>The <code>unflatten()</code> function only works for an object whose keys are JSON Pointers and whose values are primitive.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p>Calling <code>unflatten()</code> on an object <code class=highlight><span class=p>{</span><span class=s2>&quot;/1&quot;</span><span class=p>,</span><span class=w> </span><span class=p>[</span><span class=mi>1</span><span class=p>,</span><span class=mi>2</span><span class=p>,</span><span class=mi>3</span><span class=p>]}</span><span class=w></span></code>:</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.315] values in object must be primitive
</code></pre></div> </div> <h3 id=jsonexceptiontype_error314>json.exception.type_error.314<a class=headerlink href=#jsonexceptiontype_error314 title="Permanent link">&para;</a></h3> <p>The <code>unflatten</code> function only works for an object whose keys are JSON Pointers.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p>Calling <code>unflatten()</code> on an array <code class=highlight><span class=p>[</span><span class=mi>1</span><span class=p>,</span><span class=mi>2</span><span class=p>,</span><span class=mi>3</span><span class=p>]</span></code>:</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.314] only objects can be unflattened
</code></pre></div> </div> <h3 id=jsonexceptiontype_error315>json.exception.type_error.315<a class=headerlink href=#jsonexceptiontype_error315 title="Permanent link">&para;</a></h3> <p>The <code>unflatten()</code> function only works for an object whose keys are JSON Pointers and whose values are primitive.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p>Calling <code>unflatten()</code> on an object <code class=highlight><span class=p>{</span><span class=s2>&quot;/1&quot;</span><span class=p>,</span><span class=w> </span><span class=p>[</span><span class=mi>1</span><span class=p>,</span><span class=mi>2</span><span class=p>,</span><span class=mi>3</span><span class=p>]}</span></code>:</p> <div class=highlight><pre><span></span><code>[json.exception.type_error.315] values in object must be primitive
</code></pre></div> </div> <h3 id=jsonexceptiontype_error316>json.exception.type_error.316<a class=headerlink href=#jsonexceptiontype_error316 title="Permanent link">&para;</a></h3> <p>The <code>dump()</code> function only works with UTF-8 encoded strings; that is, if you assign a <code>std::string</code> to a JSON value, make sure it is UTF-8 encoded.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p>Calling <code>dump()</code> on a JSON value containing an ISO 8859-1 encoded string: <div class=highlight><pre><span></span><code>[json.exception.type_error.316] invalid UTF-8 byte at index 15: 0x6F
</code></pre></div></p> </div> <div class="admonition tip"> <p class=admonition-title>Tip</p> <ul> <li>Store the source file with UTF-8 encoding.</li> <li>Pass an error handler as last parameter to the <code>dump()</code> function to avoid this exception:<ul> <li><code>json::error_handler_t::replace</code> will replace invalid bytes sequences with <code>U+FFFD</code> </li> <li><code>json::error_handler_t::ignore</code> will silently ignore invalid byte sequences</li> </ul> </li> </ul> </div> <h3 id=jsonexceptiontype_error317>json.exception.type_error.317<a class=headerlink href=#jsonexceptiontype_error317 title="Permanent link">&para;</a></h3> <p>The dynamic type of the object cannot be represented in the requested serialization format (e.g. a raw <code>true</code> or <code>null</code> JSON object cannot be serialized to BSON)</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p>Serializing <code class=highlight><span class=kc>null</span><span class=w></span></code> to BSON: <div class=highlight><pre><span></span><code>[json.exception.type_error.317] to serialize to BSON, top-level type must be object, but is null
</code></pre></div> Serializing <code class=highlight><span class=p>[</span><span class=mi>1</span><span class=p>,</span><span class=mi>2</span><span class=p>,</span><span class=mi>3</span><span class=p>]</span><span class=w></span></code> to BSON: <div class=highlight><pre><span></span><code>[json.exception.type_error.317] to serialize to BSON, top-level type must be object, but is array
</code></pre></div></p> </div> <div class="admonition tip"> <p class=admonition-title>Tip</p> <p>Encapsulate the JSON value in an object. That is, instead of serializing <code class=highlight><span class=kc>true</span><span class=w></span></code>, serialize <code class=highlight><span class=p>{</span><span class=nt>&quot;value&quot;</span><span class=p>:</span><span class=w> </span><span class=kc>true</span><span class=p>}</span><span class=w></span></code></p> </div> <h2 id=out-of-range>Out of range<a class=headerlink href=#out-of-range title="Permanent link">&para;</a></h2> <p>This exception is thrown in case a library function is called on an input parameter that exceeds the expected range, for instance in case of array indices or nonexisting object keys.</p> <p>Exceptions have ids 4xx.</p> <details class=example> <summary>Example</summary> <p>The following code shows how an <code>out_of_range</code> exception can be caught.</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=cp></span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span><span class=cp></span>
</code></pre></div></p> </div> <div class="admonition tip"> <p class=admonition-title>Tip</p> <ul> <li>Store the source file with UTF-8 encoding.</li> <li>Pass an error handler as last parameter to the <code>dump()</code> function to avoid this exception:<ul> <li><code>json::error_handler_t::replace</code> will replace invalid bytes sequences with <code>U+FFFD</code> </li> <li><code>json::error_handler_t::ignore</code> will silently ignore invalid byte sequences</li> </ul> </li> </ul> </div> <h3 id=jsonexceptiontype_error317>json.exception.type_error.317<a class=headerlink href=#jsonexceptiontype_error317 title="Permanent link">&para;</a></h3> <p>The dynamic type of the object cannot be represented in the requested serialization format (e.g. a raw <code>true</code> or <code>null</code> JSON object cannot be serialized to BSON)</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p>Serializing <code class=highlight><span class=kc>null</span></code> to BSON: <div class=highlight><pre><span></span><code>[json.exception.type_error.317] to serialize to BSON, top-level type must be object, but is null
</code></pre></div> Serializing <code class=highlight><span class=p>[</span><span class=mi>1</span><span class=p>,</span><span class=mi>2</span><span class=p>,</span><span class=mi>3</span><span class=p>]</span></code> to BSON: <div class=highlight><pre><span></span><code>[json.exception.type_error.317] to serialize to BSON, top-level type must be object, but is array
</code></pre></div></p> </div> <div class="admonition tip"> <p class=admonition-title>Tip</p> <p>Encapsulate the JSON value in an object. That is, instead of serializing <code class=highlight><span class=kc>true</span></code>, serialize <code class=highlight><span class=p>{</span><span class=nt>&quot;value&quot;</span><span class=p>:</span><span class=w> </span><span class=kc>true</span><span class=p>}</span></code></p> </div> <h2 id=out-of-range>Out of range<a class=headerlink href=#out-of-range title="Permanent link">&para;</a></h2> <p>This exception is thrown in case a library function is called on an input parameter that exceeds the expected range, for instance in case of array indices or nonexisting object keys.</p> <p>Exceptions have ids 4xx.</p> <details class=example> <summary>Example</summary> <p>The following code shows how an <code>out_of_range</code> exception can be caught.</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=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span><span class=w></span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span><span class=w></span>
<span class=p>{</span><span class=w></span>
<span class=w> </span><span class=k>try</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span>
<span class=p>{</span>
<span class=w> </span><span class=k>try</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// calling at() for an invalid index</span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=p>{</span><span class=mi>1</span><span class=p>,</span><span class=w> </span><span class=mi>2</span><span class=p>,</span><span class=w> </span><span class=mi>3</span><span class=p>,</span><span class=w> </span><span class=mi>4</span><span class=p>};</span><span class=w></span>
<span class=w> </span><span class=n>j</span><span class=p>.</span><span class=n>at</span><span class=p>(</span><span class=mi>4</span><span class=p>)</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=mi>10</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>out_of_range</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>j</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=p>{</span><span class=mi>1</span><span class=p>,</span><span class=w> </span><span class=mi>2</span><span class=p>,</span><span class=w> </span><span class=mi>3</span><span class=p>,</span><span class=w> </span><span class=mi>4</span><span class=p>};</span>
<span class=w> </span><span class=n>j</span><span class=p>.</span><span class=n>at</span><span class=p>(</span><span class=mi>4</span><span class=p>)</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=mi>10</span><span class=p>;</span>
<span class=w> </span><span class=p>}</span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>out_of_range</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// output exception information</span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=w></span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=p>}</span><span class=w></span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span>
<span class=w> </span><span class=p>}</span>
<span class=p>}</span>
</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>message: [json.exception.out_of_range.401] array index 4 is out of range
exception id: 401
</code></pre></div> </details> <h3 id=jsonexceptionout_of_range401>json.exception.out_of_range.401<a class=headerlink href=#jsonexceptionout_of_range401 title="Permanent link">&para;</a></h3> <p>The provided array index <code>i</code> is larger than <code>size-1</code>.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>array index 3 is out of range
@@ -223,37 +223,37 @@ exception id: 401
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range407>json.exception.out_of_range.407<a class=headerlink href=#jsonexceptionout_of_range407 title="Permanent link">&para;</a></h3> <p>UBJSON and BSON only support integer numbers up to 9223372036854775807.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>number overflow serializing &#39;9223372036854775808&#39;
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>Since version 3.9.0, integer numbers beyond int64 are serialized as high-precision UBJSON numbers, and this exception does not further occur. </p> </div> <h3 id=jsonexceptionout_of_range408>json.exception.out_of_range.408<a class=headerlink href=#jsonexceptionout_of_range408 title="Permanent link">&para;</a></h3> <p>The size (following <code>#</code>) of an UBJSON array or object exceeds the maximal capacity.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>excessive array size: 8658170730974374167
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range409>json.exception.out_of_range.409<a class=headerlink href=#jsonexceptionout_of_range409 title="Permanent link">&para;</a></h3> <p>Key identifiers to be serialized to BSON cannot contain code point U+0000, since the key is stored as zero-terminated c-string.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>BSON key cannot contain code point U+0000 (at byte 2)
</code></pre></div> </div> <h2 id=further-exceptions>Further exceptions<a class=headerlink href=#further-exceptions title="Permanent link">&para;</a></h2> <p>This exception is thrown in case of errors that cannot be classified with the other exception types.</p> <p>Exceptions have ids 5xx.</p> <details class=example> <summary>Example</summary> <p>The following code shows how an <code>other_error</code> exception can be caught.</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=cp></span>
<span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span><span class=cp></span>
</code></pre></div> </div> <h2 id=further-exceptions>Further exceptions<a class=headerlink href=#further-exceptions title="Permanent link">&para;</a></h2> <p>This exception is thrown in case of errors that cannot be classified with the other exception types.</p> <p>Exceptions have ids 5xx.</p> <details class=example> <summary>Example</summary> <p>The following code shows how an <code>other_error</code> exception can be caught.</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=cp>#include</span><span class=w> </span><span class=cpf>&lt;nlohmann/json.hpp&gt;</span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span><span class=w></span>
<span class=k>using</span><span class=w> </span><span class=k>namespace</span><span class=w> </span><span class=nn>nlohmann</span><span class=o>::</span><span class=nn>literals</span><span class=p>;</span><span class=w></span>
<span class=k>using</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>nlohmann</span><span class=o>::</span><span class=n>json</span><span class=p>;</span>
<span class=k>using</span><span class=w> </span><span class=k>namespace</span><span class=w> </span><span class=nn>nlohmann</span><span class=o>::</span><span class=nn>literals</span><span class=p>;</span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span><span class=w></span>
<span class=p>{</span><span class=w></span>
<span class=w> </span><span class=k>try</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span>
<span class=p>{</span>
<span class=w> </span><span class=k>try</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// executing a failing JSON Patch operation</span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>value</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=sa>R</span><span class=s>&quot;</span><span class=dl>(</span><span class=s>{</span>
<span class=s> &quot;best_biscuit&quot;: {</span>
<span class=s> &quot;name&quot;: &quot;Oreo&quot;</span>
<span class=s> }</span>
<span class=s> }</span><span class=dl>)</span><span class=s>&quot;</span><span class=n>_json</span><span class=p>;</span><span class=w></span>
<span class=s> }</span><span class=dl>)</span><span class=s>&quot;</span><span class=n>_json</span><span class=p>;</span>
<span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>patch</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=sa>R</span><span class=s>&quot;</span><span class=dl>(</span><span class=s>[{</span>
<span class=s> &quot;op&quot;: &quot;test&quot;,</span>
<span class=s> &quot;path&quot;: &quot;/best_biscuit/name&quot;,</span>
<span class=s> &quot;value&quot;: &quot;Choco Leibniz&quot;</span>
<span class=s> }]</span><span class=dl>)</span><span class=s>&quot;</span><span class=n>_json</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=n>value</span><span class=p>.</span><span class=n>patch</span><span class=p>(</span><span class=n>patch</span><span class=p>);</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>other_error</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span><span class=w></span>
<span class=w> </span><span class=p>{</span><span class=w></span>
<span class=s> }]</span><span class=dl>)</span><span class=s>&quot;</span><span class=n>_json</span><span class=p>;</span>
<span class=w> </span><span class=n>value</span><span class=p>.</span><span class=n>patch</span><span class=p>(</span><span class=n>patch</span><span class=p>);</span>
<span class=w> </span><span class=p>}</span>
<span class=w> </span><span class=k>catch</span><span class=w> </span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=o>::</span><span class=n>other_error</span><span class=o>&amp;</span><span class=w> </span><span class=n>e</span><span class=p>)</span>
<span class=w> </span><span class=p>{</span>
<span class=w> </span><span class=c1>// output exception information</span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span><span class=w></span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span><span class=w></span>
<span class=w> </span><span class=p>}</span><span class=w></span>
<span class=p>}</span><span class=w></span>
<span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>cout</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;message: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>what</span><span class=p>()</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=sc>&#39;\n&#39;</span>
<span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=s>&quot;exception id: &quot;</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>e</span><span class=p>.</span><span class=n>id</span><span class=w> </span><span class=o>&lt;&lt;</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>endl</span><span class=p>;</span>
<span class=w> </span><span class=p>}</span>
<span class=p>}</span>
</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code>message: [json.exception.other_error.501] unsuccessful: {&quot;op&quot;:&quot;test&quot;,&quot;path&quot;:&quot;/best_biscuit/name&quot;,&quot;value&quot;:&quot;Choco Leibniz&quot;}
exception id: 501
</code></pre></div> </details> <h3 id=jsonexceptionother_error501>json.exception.other_error.501<a class=headerlink href=#jsonexceptionother_error501 title="Permanent link">&para;</a></h3> <p>A JSON Patch operation 'test' failed. The unsuccessful operation is also printed.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p>Executing <code class=highlight><span class=p>{</span><span class=nt>&quot;op&quot;</span><span class=p>:</span><span class=s2>&quot;test&quot;</span><span class=p>,</span><span class=w> </span><span class=nt>&quot;path&quot;</span><span class=p>:</span><span class=s2>&quot;/baz&quot;</span><span class=p>,</span><span class=w> </span><span class=nt>&quot;value&quot;</span><span class=p>:</span><span class=s2>&quot;bar&quot;</span><span class=p>}</span><span class=w></span></code> on <code class=highlight><span class=p>{</span><span class=nt>&quot;baz&quot;</span><span class=p>:</span><span class=w> </span><span class=s2>&quot;qux&quot;</span><span class=p>}</span><span class=w></span></code>:</p> <div class=highlight><pre><span></span><code>[json.exception.other_error.501] unsuccessful: {&quot;op&quot;:&quot;test&quot;,&quot;path&quot;:&quot;/baz&quot;,&quot;value&quot;:&quot;bar&quot;}
</code></pre></div> </div> <hr> <div class=md-source-file> <small> Last update: <span class="git-revision-date-localized-plugin git-revision-date-localized-plugin-date">July 31, 2022</span> </small> </div> </article> </div> <script>var tabs=__md_get("__tabs");if(Array.isArray(tabs))e:for(var set of document.querySelectorAll(".tabbed-set")){var tab,labels=set.querySelector(".tabbed-labels");for(tab of tabs)for(var label of labels.getElementsByTagName("label"))if(label.innerText.trim()===tab){var input=document.getElementById(label.htmlFor);input.checked=!0;continue e}}</script> </div> <a href=# class="md-top md-icon" data-md-component=top hidden> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M13 20h-2V8l-5.5 5.5-1.42-1.42L12 4.16l7.92 7.92-1.42 1.42L13 8v12Z"/></svg> Back to top </a> </main> <footer class=md-footer> <nav class="md-footer__inner md-grid" aria-label=Footer> <a href=../faq/ class="md-footer__link md-footer__link--prev" aria-label="Previous: FAQ" rel=prev> <div class="md-footer__button md-icon"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M20 11v2H8l5.5 5.5-1.42 1.42L4.16 12l7.92-7.92L13.5 5.5 8 11h12Z"/></svg> </div> <div class=md-footer__title> <div class=md-ellipsis> <span class=md-footer__direction> Previous </span> FAQ </div> </div> </a> <a href=../releases/ class="md-footer__link md-footer__link--next" aria-label="Next: Releases" rel=next> <div class=md-footer__title> <div class=md-ellipsis> <span class=md-footer__direction> Next </span> Releases </div> </div> <div class="md-footer__button md-icon"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M4 11v2h12l-5.5 5.5 1.42 1.42L19.84 12l-7.92-7.92L10.5 5.5 16 11H4Z"/></svg> </div> </a> </nav> <div class="md-footer-meta md-typeset"> <div class="md-footer-meta__inner md-grid"> <div class=md-copyright> <div class=md-copyright__highlight> Copyright &copy; 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</code></pre></div> </details> <h3 id=jsonexceptionother_error501>json.exception.other_error.501<a class=headerlink href=#jsonexceptionother_error501 title="Permanent link">&para;</a></h3> <p>A JSON Patch operation 'test' failed. The unsuccessful operation is also printed.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p>Executing <code class=highlight><span class=p>{</span><span class=nt>&quot;op&quot;</span><span class=p>:</span><span class=s2>&quot;test&quot;</span><span class=p>,</span><span class=w> </span><span class=nt>&quot;path&quot;</span><span class=p>:</span><span class=s2>&quot;/baz&quot;</span><span class=p>,</span><span class=w> </span><span class=nt>&quot;value&quot;</span><span class=p>:</span><span class=s2>&quot;bar&quot;</span><span class=p>}</span></code> on <code class=highlight><span class=p>{</span><span class=nt>&quot;baz&quot;</span><span class=p>:</span><span class=w> </span><span class=s2>&quot;qux&quot;</span><span class=p>}</span></code>:</p> <div class=highlight><pre><span></span><code>[json.exception.other_error.501] unsuccessful: {&quot;op&quot;:&quot;test&quot;,&quot;path&quot;:&quot;/baz&quot;,&quot;value&quot;:&quot;bar&quot;}
</code></pre></div> </div> <hr> <div class=md-source-file> <small> Last update: <span class="git-revision-date-localized-plugin git-revision-date-localized-plugin-date">October 31, 2023</span> </small> </div> </article> </div> <script>var tabs=__md_get("__tabs");if(Array.isArray(tabs))e:for(var set of document.querySelectorAll(".tabbed-set")){var tab,labels=set.querySelector(".tabbed-labels");for(tab of tabs)for(var label of labels.getElementsByTagName("label"))if(label.innerText.trim()===tab){var input=document.getElementById(label.htmlFor);input.checked=!0;continue e}}</script> </div> <button type=button class="md-top md-icon" data-md-component=top hidden> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M13 20h-2V8l-5.5 5.5-1.42-1.42L12 4.16l7.92 7.92-1.42 1.42L13 8v12Z"/></svg> Back to top </button> </main> <footer class=md-footer> <div class="md-footer-meta md-typeset"> <div class="md-footer-meta__inner md-grid"> <div class=md-copyright> <div class=md-copyright__highlight> Copyright &copy; 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