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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-1.6.1, mkdocs-material-9.7.7"><title>Exceptions - 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 URL("../..",location),__md_hash=e=>[...e].reduce(((e,_)=>(e<<5)-e+_.charCodeAt(0)),0),__md_get=(e,_=localStorage,t=__md_scope)=>JSON.parse(_.getItem(t.pathname+"."+e)),__md_set=(e,_,t=localStorage,a=__md_scope)=>{try{t.setItem(a.pathname+"."+e,JSON.stringify(_))}catch(e){}}</script></head> <body dir=ltr data-md-color-scheme=default data-md-color-primary=indigo data-md-color-accent=indigo> <input class=md-toggle data-md-toggle=drawer type=checkbox id=__drawer autocomplete=off> <input class=md-toggle data-md-toggle=search type=checkbox id=__search autocomplete=off> <label class=md-overlay for=__drawer></label> <div data-md-component=skip> <a href=#exceptions class=md-skip> Skip to content </a> </div> <div data-md-component=announce> </div> <header class=md-header data-md-component=header> <nav class="md-header__inner md-grid" aria-label=Header> <a href=../.. title="JSON for Modern C++" class="md-header__button md-logo" aria-label="JSON for Modern C++" 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> Exceptions </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 mode" type=radio 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15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12z"/></svg> </label> </form> <script>var palette=__md_get("__palette");if(palette&&palette.color){if("(prefers-color-scheme)"===palette.color.media){var media=matchMedia("(prefers-color-scheme: light)"),input=document.querySelector(media.matches?"[data-md-color-media='(prefers-color-scheme: light)']":"[data-md-color-media='(prefers-color-scheme: dark)']");palette.color.media=input.getAttribute("data-md-color-media"),palette.color.scheme=input.getAttribute("data-md-color-scheme"),palette.color.primary=input.getAttribute("data-md-color-primary"),palette.color.accent=input.getAttribute("data-md-color-accent")}for(var[key,value]of Object.entries(palette.color))document.body.setAttribute("data-md-color-"+key,value)}</script> <label class="md-header__button md-icon" for=__search> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M9.5 3A6.5 6.5 0 0 1 16 9.5c0 1.61-.59 3.09-1.56 4.23l.27.27h.79l5 5-1.5 1.5-5-5v-.79l-.27-.27A6.52 6.52 0 0 1 9.5 16 6.5 6.5 0 0 1 3 9.5 6.5 6.5 0 0 1 9.5 3m0 2C7 5 5 7 5 9.5S7 14 9.5 14 14 12 14 9.5 12 5 9.5 5"/></svg> </label> <div class=md-search data-md-componLine truncated
direction LR
class `std::exception` {
&lt;&lt;interface&gt;&gt;
}
class `json::exception` {
+const int id
+const char* what() const
}
class `json::parse_error` {
+const std::size_t byte
}
class `json::invalid_iterator`
class `json::type_error`
class `json::out_of_range`
class `json::other_error`
`std::exception` &lt;|-- `json::exception`
`json::exception` &lt;|-- `json::parse_error`
`json::exception` &lt;|-- `json::invalid_iterator`
`json::exception` &lt;|-- `json::type_error`
`json::exception` &lt;|-- `json::out_of_range`
`json::exception` &lt;|-- `json::other_error`</code></pre> <h3 id=switch-off-exceptions>Switch off exceptions<a class=headerlink href=#switch-off-exceptions title="Permanent link">&para;</a></h3> <p>Exceptions are used widely within the library. They can, however, be switched off with either using the compiler flag <code>-fno-exceptions</code> or by defining the symbol <a href=../../api/macros/json_noexception/ ><code>JSON_NOEXCEPTION</code></a>. In this case, exceptions are replaced by <code>abort()</code> calls. You can further control this behavior by defining <code>JSON_THROW_USER</code> (overriding <code class=highlight><span class=k>throw</span></code>), <code>JSON_TRY_USER</code> (overriding <code class=highlight><span class=k>try</span></code>), and <code>JSON_CATCH_USER</code> (overriding <code class=highlight><span class=k>catch</span></code>).</p> <p>See <a href=../../features/no_exceptions/ >Working without exceptions</a> for the functions that report errors without throwing.</p> <p>Note that <a href=../../api/macros/json_throw_user/ ><code>JSON_THROW_USER</code></a> should leave the current scope (e.g., by throwing or aborting), as continuing after it may yield undefined behavior.</p> <details class=example> <summary>Example: switch off exceptions and log errors before aborting</summary> <p>The code below switches off exceptions and creates a log entry with a detailed error message in case of errors.</p> <div class=highlight><pre><span></span><code><span class=cp>#include</span><span class=w> </span><span class=cpf>&lt;iostream&gt;</span>
<!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=description content="JSON for Modern C++ is a header-only C++11 library that makes JSON a first-class data type."><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-1.6.1, mkdocs-material-9.7.7"><title>Exceptions - 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=../../css/custom.css><link rel=stylesheet href=../../css/brand.css><link rel=stylesheet href=../../css/fig-sax.css><link rel=stylesheet href=../../css/fig-jsonview.css><link rel=stylesheet href=../../css/fig-exceptions.css><link rel=stylesheet href=../../css/fig-pointer.css><link rel=stylesheet href=../../css/fig-charts.css><link rel=stylesheet href=../../css/fig-integration.css><link rel=stylesheet href=../../css/fig-macros.css><script>__md_scope=new URL("../..",location),__md_hash=e=>[...e].reduce(((e,_)=>(e<<5)-e+_.charCodeAt(0)),0),__md_get=(e,_=localStorage,t=__md_scope)=>JSON.parse(_.getItem(t.pathname+"."+e)),__md_set=(e,_,t=localStorage,a=__md_scope)=>{try{t.setItem(a.pathname+"."+e,JSON.stringify(_))}catch(e){}}</script></head> <body dir=ltr data-md-color-scheme=default data-md-color-primary=custom data-md-color-accent=custom> <input class=md-toggle data-md-toggle=drawer type=checkbox id=__drawer autocomplete=off> <input class=md-toggle data-md-toggle=search type=checkbox id=__search autocomplete=off> <label class=md-overlay for=__drawer></label> <div data-md-component=skip> <a href=#exceptions class=md-skip> Skip to content </a> </div> <div data-md-component=announce> </div> <header class=md-header data-md-component=header> <nav class="md-header__inner md-grid" aria-label=Header> <a href=../.. title="JSON for Modern C++" class="md-header__button md-logo" aria-label="JSON for Modern C++" data-md-component=logo> <img src=../../images/wordmark-header.svg alt=logo> </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> Exceptions </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 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12s-1.44-4.5-3.5-5.45C10.26 6.2 11.11 6 12 6a6 6 0 0 1 6 6 6 6 0 0 1-6 6m8-9.31V4h-4.69L12 .69 8.69 4H4v4.69L.69 12 4 15.31V20h4.69L12 23.31 15.31 20H20v-4.69L23.31 12z"/></svg> </label> </form> <script>var palette=__md_get("__palette");if(palette&&palette.color){if("(prefers-color-scheme)"===palette.color.media){var media=matchMedia("(prefers-color-scheme: light)"),input=document.querySelector(media.matches?"[data-md-color-media='(prefers-color-scheme: light)']":"[data-md-color-media='(prefers-color-scheme: dark)']");palette.color.media=input.getAttribute("data-md-color-media"),palette.color.scheme=input.getAttribute("data-md-color-scheme"),palette.color.primary=input.getAttribute("data-md-color-primary"),palette.color.accent=input.getAttribute("data-md-color-accent")}for(var[key,value]of Object.entries(palette.color))document.body.setAttribute("data-md-color-"+key,value)}</script> <label class="md-header__button md-icon" for=__search> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M9.5 3A6.5 6.5 0 0 1 16 9.5c0 1.61-.59 3.09-1.56 4.23l.27.27h.79l5 5-1.5 1.5-5-5v-.79lLine truncated
S{{"which call?"}} --&gt;|"at(key)"| A{{"j is"}}
A --&gt;|"object, key missing"| A1["out_of_range.403"]
A --&gt;|"array or null"| A2["type_error.304"]
S --&gt;|"at(index)"| B{{"j is"}}
B --&gt;|"array, index &gt;= size()"| B1["out_of_range.401"]
B --&gt;|"object or null"| B2["type_error.304"]
S --&gt;|"non-const operator[](key)"| C{{"j is"}}
C --&gt;|"object or null"| C1["no exception: a missing key is inserted as null"]
C --&gt;|"array"| C2["type_error.305"]
S --&gt;|"value(key, default)"| D{{"j is"}}
D --&gt;|"object, key missing"| D1["no exception: returns the default"]
D --&gt;|"object, incompatible value type"| D2["type_error.302"]
D --&gt;|"array or null"| D3["type_error.306"]</code></pre> <p class=nj-caption>Exceptions thrown by element access. Start at the call on the left, follow the edge that matches the type of <code>j</code>, and read the exception id (or "no exception") in the box at the end.</p> <h3 id=switch-off-exceptions>Switch off exceptions<a class=headerlink href=#switch-off-exceptions title="Permanent link">&para;</a></h3> <p>Exceptions are used widely within the library. They can, however, be switched off with either using the compiler flag <code>-fno-exceptions</code> or by defining the symbol <a href=../../api/macros/json_noexception/ ><code>JSON_NOEXCEPTION</code></a>. In this case, exceptions are replaced by <code>abort()</code> calls. You can further control this behavior by defining <code>JSON_THROW_USER</code> (overriding <code class=highlight><span class=k>throw</span></code>), <code>JSON_TRY_USER</code> (overriding <code class=highlight><span class=k>try</span></code>), and <code>JSON_CATCH_USER</code> (overriding <code class=highlight><span class=k>catch</span></code>).</p> <p>See <a href=../../features/no_exceptions/ >Working without exceptions</a> for the functions that report errors without throwing.</p> <p>Note that <a href=../../api/macros/json_throw_user/ ><code>JSON_THROW_USER</code></a> should leave the current scope (e.g., by throwing or aborting), as continuing after it may yield undefined behavior.</p> <details class=example> <summary>Example: switch off exceptions and log errors before aborting</summary> <p>The code below switches off exceptions and creates a log entry with a detailed error message in case of errors.</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>#define JSON_TRY_USER if(true)</span>
<span class=cp>#define JSON_CATCH_USER(exception) if(false)</span>
@@ -116,8 +104,8 @@ byte position of error: 8
<span class=w> </span><span class=k>return</span><span class=w> </span><span class=mi>1</span><span class=p>;</span>
<span class=p>}</span>
<span class=n>json</span><span class=w> </span><span class=n>data</span><span class=w> </span><span class=o>=</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=n>f</span><span class=p>);</span>
</code></pre></div> </details> <h3 id=jsonexceptionparse_error102>json.exception.parse_error.102<a class=headerlink href=#jsonexceptionparse_error102 title="Permanent link">&para;</a></h3> <p><abbr title="JavaScript Object Notation">JSON</abbr> uses the <code>\uxxxx</code> format to describe Unicode characters. Code points above 0xFFFF are split into two <code>\uxxxx</code> entries ("surrogate pairs"). This error indicates that the surrogate pair is incomplete or contains an invalid code point.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>parse error at 14: missing or wrong low surrogate
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception is not used any more. Instead <a href=#jsonexceptionparse_error101>json.exception.parse_error.101</a> with a more detailed description is used.</p> </div> <h3 id=jsonexceptionparse_error103>json.exception.parse_error.103<a class=headerlink href=#jsonexceptionparse_error103 title="Permanent link">&para;</a></h3> <p>Unicode supports code points up to 0x10FFFF. Code points above 0x10FFFF are invalid.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>parse error: code points above 0x10FFFF are invalid
</code></pre></div> </details> <h3 id=jsonexceptionparse_error102>json.exception.parse_error.102<a class=headerlink href=#jsonexceptionparse_error102 title="Permanent link">&para;</a></h3> <p><abbr title="JavaScript Object Notation">JSON</abbr> uses the <code>\uxxxx</code> format to describe Unicode characters. Code points above 0xFFFF are split into two <code>\uxxxx</code> entries ("surrogate pairs"). This error indicates that the surrogate pair is incomplete or contains an invalid code point.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.102] parse error at 14: missing or wrong low surrogate
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception is not used any more. Instead <a href=#jsonexceptionparse_error101>json.exception.parse_error.101</a> with a more detailed description is used.</p> </div> <h3 id=jsonexceptionparse_error103>json.exception.parse_error.103<a class=headerlink href=#jsonexceptionparse_error103 title="Permanent link">&para;</a></h3> <p>Unicode supports code points up to 0x10FFFF. Code points above 0x10FFFF are invalid.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.103] parse error: code points above 0x10FFFF are invalid
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception is not used any more. Instead <a href=#jsonexceptionparse_error101>json.exception.parse_error.101</a> with a more detailed description is used.</p> </div> <h3 id=jsonexceptionparse_error104>json.exception.parse_error.104<a class=headerlink href=#jsonexceptionparse_error104 title="Permanent link">&para;</a></h3> <p><a href="https://tools.ietf.org/html/rfc6902"><abbr title="Request for Comments">RFC</abbr> 6902</a> requires a <abbr title="JavaScript Object Notation">JSON</abbr> Patch document to be a <abbr title="JavaScript Object Notation">JSON</abbr> document that represents an array of objects.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.parse_error.104] parse error: JSON patch must be an array of objects
</code></pre></div> </div> <h3 id=jsonexceptionparse_error105>json.exception.parse_error.105<a class=headerlink href=#jsonexceptionparse_error105 title="Permanent link">&para;</a></h3> <p>An operation of a <abbr title="JavaScript Object Notation">JSON</abbr> Patch document must contain exactly one "op" member, whose value indicates the operation to perform. Its value must be one of "add", "remove", "replace", "move", "copy", or "test"; other values are errors.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <p><div class=highlight><pre><span></span><code>[json.exception.parse_error.105] parse error: operation 'add' must have member 'value'
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.parse_error.105] parse error: operation 'copy' must have string member 'from'
@@ -258,27 +246,27 @@ exception id: 308
<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
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range402>json.exception.out_of_range.402<a class=headerlink href=#jsonexceptionout_of_range402 title="Permanent link">&para;</a></h3> <p>The special array index <code>-</code> in a <abbr title="JavaScript Object Notation">JSON</abbr> Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it.</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
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range403>json.exception.out_of_range.403<a class=headerlink href=#jsonexceptionout_of_range403 title="Permanent link">&para;</a></h3> <p>The provided key was not found in the <abbr title="JavaScript Object Notation">JSON</abbr> object.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>key 'foo' not found
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range404>json.exception.out_of_range.404<a class=headerlink href=#jsonexceptionout_of_range404 title="Permanent link">&para;</a></h3> <p>A reference token in a <abbr title="JavaScript Object Notation">JSON</abbr> Pointer could not be resolved, for instance an array index that begins with a digit but contains other characters (e.g., <code>1a</code>), or <code>-</code> where it cannot be used.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>unresolved reference token 'foo'
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range405>json.exception.out_of_range.405<a class=headerlink href=#jsonexceptionout_of_range405 title="Permanent link">&para;</a></h3> <p>The <abbr title="JavaScript Object Notation">JSON</abbr> Patch operations 'remove' and 'move' cannot be applied to the root element of the <abbr title="JavaScript Object Notation">JSON</abbr> value. The exception is also thrown when the parent or a reference token of an empty <abbr title="JavaScript Object Notation">JSON</abbr> Pointer is requested, for instance by <a href=../../api/json_pointer/back/ ><code>back</code></a> or <a href=../../api/json_pointer/pop_back/ ><code>pop_back</code></a>.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>JSON pointer has no parent
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range406>json.exception.out_of_range.406<a class=headerlink href=#jsonexceptionout_of_range406 title="Permanent link">&para;</a></h3> <p>A parsed number could not be stored without changing it to <abbr title="Not a Number">NaN</abbr> or INF. For the binary formats, this happens when a finite floating-point number does not fit into <a href=../../api/basic_json/number_float_t/ ><code>number_float_t</code></a>, for example a double-precision number when <code>number_float_t</code> is <code class=highlight><span class=kt>float</span></code>.</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>number overflow parsing '10E1000'
</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>[json.exception.out_of_range.401] array index 3 is out of range
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range402>json.exception.out_of_range.402<a class=headerlink href=#jsonexceptionout_of_range402 title="Permanent link">&para;</a></h3> <p>The special array index <code>-</code> in a <abbr title="JavaScript Object Notation">JSON</abbr> Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.402] array index '-' (3) is out of range
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range403>json.exception.out_of_range.403<a class=headerlink href=#jsonexceptionout_of_range403 title="Permanent link">&para;</a></h3> <p>The provided key was not found in the <abbr title="JavaScript Object Notation">JSON</abbr> object.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.403] key 'foo' not found
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range404>json.exception.out_of_range.404<a class=headerlink href=#jsonexceptionout_of_range404 title="Permanent link">&para;</a></h3> <p>A reference token in a <abbr title="JavaScript Object Notation">JSON</abbr> Pointer could not be resolved, for instance an array index that begins with a digit but contains other characters (e.g., <code>1a</code>), or <code>-</code> where it cannot be used.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.404] unresolved reference token 'foo'
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range405>json.exception.out_of_range.405<a class=headerlink href=#jsonexceptionout_of_range405 title="Permanent link">&para;</a></h3> <p>The <abbr title="JavaScript Object Notation">JSON</abbr> Patch operations 'remove' and 'move' cannot be applied to the root element of the <abbr title="JavaScript Object Notation">JSON</abbr> value. The exception is also thrown when the parent or a reference token of an empty <abbr title="JavaScript Object Notation">JSON</abbr> Pointer is requested, for instance by <a href=../../api/json_pointer/back/ ><code>back</code></a> or <a href=../../api/json_pointer/pop_back/ ><code>pop_back</code></a>.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.405] JSON pointer has no parent
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range406>json.exception.out_of_range.406<a class=headerlink href=#jsonexceptionout_of_range406 title="Permanent link">&para;</a></h3> <p>A parsed number could not be stored without changing it to <abbr title="Not a Number">NaN</abbr> or INF. For the binary formats, this happens when a finite floating-point number does not fit into <a href=../../api/basic_json/number_float_t/ ><code>number_float_t</code></a>, for example a double-precision number when <code>number_float_t</code> is <code class=highlight><span class=kt>float</span></code>.</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>[json.exception.out_of_range.406] number overflow parsing '10E1000'
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.406] syntax error while parsing CBOR value: number overflow
</code></pre></div></p> </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>An integer number cannot be represented by the binary format it is serialized to:</p> <ul> <li><a href=../../features/binary_formats/bon8/ ><abbr title="Binary Object Notation 8">BON8</abbr></a> only stores integers that fit into int64, so <a href=../../api/basic_json/to_bon8/ ><code>to_bon8</code></a> throws for unsigned integers greater than 9223372036854775807 and, with a number type wider than 64 bits, for any integer outside the int64 range.</li> <li><a href=../../features/binary_formats/cbor/ ><abbr title="Concise Binary Object Representation">CBOR</abbr></a>, <a href=../../features/binary_formats/messagepack/ >MessagePack</a>, and <a href=../../features/binary_formats/bson/ ><abbr title="Binary JSON">BSON</abbr></a> store integers in at most 64 bits. With the default number types, every integer fits, but a <a href=../../api/basic_json/number_integer_t/ ><code>number_integer_t</code></a> or <a href=../../api/basic_json/number_unsigned_t/ ><code>number_unsigned_t</code></a> wider than 64 bits (e.g., <code>__int128</code>) can hold values outside the range of the format: [-2^64, 2^64-1] for <abbr title="Concise Binary Object Representation">CBOR</abbr>, [-2^63, 2^64-1] for MessagePack, and the range of int64 (signed integers) or uint64 (unsigned integers) for <abbr title="Binary JSON">BSON</abbr>.</li> </ul> <p><a href=../../features/binary_formats/ubjson/ ><abbr title="Universal Binary JSON">UBJSON</abbr></a> and <a href=../../features/binary_formats/bjdata/ ><abbr title="Binary JData">BJData</abbr></a> never throw this exception, because they serialize integers beyond 64 bits as high-precision numbers.</p> <div class="admonition note"> <p class=admonition-title>Former occurrences</p> <p>The <abbr title="Universal Binary JSON">UBJSON</abbr> and <abbr title="Binary JSON">BSON</abbr> writers used to throw this exception as well:</p> <ul> <li>Since version 3.9.0, integer numbers beyond int64 are serialized as high-precision <abbr title="Universal Binary JSON">UBJSON</abbr> numbers.</li> <li>Since version 3.12.0, integer numbers beyond int64 are serialized as uint64 <abbr title="Binary JSON">BSON</abbr> numbers.</li> </ul> <p>Before version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>, <abbr title="Concise Binary Object Representation">CBOR</abbr>, MessagePack, and <abbr title="Binary JSON">BSON</abbr> silently truncated integers wider than 64 bits, and <abbr title="Binary JData">BJData</abbr> truncated unsigned integers wider than 64 bits that were elements of ND-arrays with <code>"_ArrayType_": "uint64"</code>.</p> </div> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>integer number 18446744073709551615 cannot be represented by BON8 as it does not fit int64
</code></pre></div> <div class=highlight><pre><span></span><code>integer number 1267650600228229401496703205376 cannot be represented by CBOR as it does not fit [-2^64, 2^64-1]
</code></pre></div></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 of an array or object in a <a href=../../features/binary_formats/ >binary format</a> exceeds the maximal capacity: the size following <code>#</code> for <a href=../../features/binary_formats/ubjson/ ><abbr title="Universal Binary JSON">UBJSON</abbr></a>/<a href=../../features/binary_formats/bjdata/ ><abbr title="Binary JData">BJData</abbr></a>, or the encoded length for <a href=../../features/binary_formats/cbor/ ><abbr title="Concise Binary Object Representation">CBOR</abbr></a>.</p> <p>The exception is also thrown for a <a href=../../features/binary_formats/ubjson/ ><abbr title="Universal Binary JSON">UBJSON</abbr></a> array of a type that is encoded by its marker alone (<code>Z</code>, <code>T</code> or <code>F</code>) whose declared count exceeds 1,048,576 (<code>1 &lt;&lt; 20</code>). Such an array has no payload, so its count alone decides how much memory is allocated, and a handful of bytes would otherwise describe billions of values. <a href=../../api/basic_json/to_ubjson/ ><code>to_ubjson</code></a> writes longer arrays of these types without the <code>$</code> type annotation (the <code>#</code> count and one marker per element are kept), so any value it produces can still be read back.</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>excessive array size: 8658170730974374167
</code></pre></div></p> </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>An integer number cannot be represented by the binary format it is serialized to:</p> <ul> <li><a href=../../features/binary_formats/bon8/ ><abbr title="Binary Object Notation 8">BON8</abbr></a> only stores integers that fit into int64, so <a href=../../api/basic_json/to_bon8/ ><code>to_bon8</code></a> throws for unsigned integers greater than 9223372036854775807 and, with a number type wider than 64 bits, for any integer outside the int64 range.</li> <li><a href=../../features/binary_formats/cbor/ ><abbr title="Concise Binary Object Representation">CBOR</abbr></a>, <a href=../../features/binary_formats/messagepack/ >MessagePack</a>, and <a href=../../features/binary_formats/bson/ ><abbr title="Binary JSON">BSON</abbr></a> store integers in at most 64 bits. With the default number types, every integer fits, but a <a href=../../api/basic_json/number_integer_t/ ><code>number_integer_t</code></a> or <a href=../../api/basic_json/number_unsigned_t/ ><code>number_unsigned_t</code></a> wider than 64 bits (e.g., <code>__int128</code>) can hold values outside the range of the format: [-2^64, 2^64-1] for <abbr title="Concise Binary Object Representation">CBOR</abbr>, [-2^63, 2^64-1] for MessagePack, and the range of int64 (signed integers) or uint64 (unsigned integers) for <abbr title="Binary JSON">BSON</abbr>.</li> </ul> <p><a href=../../features/binary_formats/ubjson/ ><abbr title="Universal Binary JSON">UBJSON</abbr></a> and <a href=../../features/binary_formats/bjdata/ ><abbr title="Binary JData">BJData</abbr></a> never throw this exception, because they serialize integers beyond 64 bits as high-precision numbers.</p> <div class="admonition note"> <p class=admonition-title>Former occurrences</p> <p>The <abbr title="Universal Binary JSON">UBJSON</abbr> and <abbr title="Binary JSON">BSON</abbr> writers used to throw this exception as well:</p> <ul> <li>Since version 3.9.0, integer numbers beyond int64 are serialized as high-precision <abbr title="Universal Binary JSON">UBJSON</abbr> numbers.</li> <li>Since version 3.12.0, integer numbers beyond int64 are serialized as uint64 <abbr title="Binary JSON">BSON</abbr> numbers.</li> </ul> <p>Before version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>, <abbr title="Concise Binary Object Representation">CBOR</abbr>, MessagePack, and <abbr title="Binary JSON">BSON</abbr> silently truncated integers wider than 64 bits, and <abbr title="Binary JData">BJData</abbr> truncated unsigned integers wider than 64 bits that were elements of ND-arrays with <code>"_ArrayType_": "uint64"</code>.</p> </div> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>[json.exception.out_of_range.407] integer number 18446744073709551615 cannot be represented by BON8 as it does not fit int64
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.407] integer number 1267650600228229401496703205376 cannot be represented by CBOR as it does not fit [-2^64, 2^64-1]
</code></pre></div></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 of an array or object in a <a href=../../features/binary_formats/ >binary format</a> exceeds the maximal capacity: the size following <code>#</code> for <a href=../../features/binary_formats/ubjson/ ><abbr title="Universal Binary JSON">UBJSON</abbr></a>/<a href=../../features/binary_formats/bjdata/ ><abbr title="Binary JData">BJData</abbr></a>, or the encoded length for <a href=../../features/binary_formats/cbor/ ><abbr title="Concise Binary Object Representation">CBOR</abbr></a>.</p> <p>The exception is also thrown for a <a href=../../features/binary_formats/ubjson/ ><abbr title="Universal Binary JSON">UBJSON</abbr></a> array of a type that is encoded by its marker alone (<code>Z</code>, <code>T</code> or <code>F</code>) whose declared count exceeds 1,048,576 (<code>1 &lt;&lt; 20</code>). Such an array has no payload, so its count alone decides how much memory is allocated, and a handful of bytes would otherwise describe billions of values. <a href=../../api/basic_json/to_ubjson/ ><code>to_ubjson</code></a> writes longer arrays of these types without the <code>$</code> type annotation (the <code>#</code> count and one marker per element are kept), so any value it produces can still be read back.</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>[json.exception.out_of_range.408] excessive array size: 8658170730974374167
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.408] syntax error while parsing CBOR size: excessive array size
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.408] syntax error while parsing CBOR size: excessive map size
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.408] syntax error while parsing UBJSON size: excessive array size
</code></pre></div></p> </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 <abbr title="Binary JSON">BSON</abbr> 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> <h3 id=jsonexceptionout_of_range410>json.exception.out_of_range.410<a class=headerlink href=#jsonexceptionout_of_range410 title="Permanent link">&para;</a></h3> <p>This exception is thrown when an undefined value is used with <a href=../../api/macros/nlohmann_json_serialize_enum_strict/ ><code>NLOHMANN_JSON_SERIALIZE_ENUM_STRICT</code></a>, or when an array index in a <abbr title="JavaScript Object Notation">JSON</abbr> pointer exceeds the range of <code>size_type</code> (e.g., on 32-bit platforms).</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>enum value out of range
array index 18446744073709551615 exceeds size_type
</code></pre></div> <p>The second message is thrown, for instance, by <code class=highlight><span class=n>json</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=s>"[1, 2]"</span><span class=p>).</span><span class=n>at</span><span class=p>(</span><span class=s>"/18446744073709551615"</span><span class=n>_json_pointer</span><span class=p>)</span></code> on a 64-bit platform, where <code>size_type</code> is <code class=highlight><span class=n>std</span><span class=o>::</span><span class=kt>size_t</span></code> and this index is <code>SIZE_MAX</code>. An index that does not fit into 64 bits (such as <code>18446744073709551616</code>) is not reported as 410 but as <a href=#jsonexceptionout_of_range404><code>out_of_range.404</code></a>.</p> </div> <h3 id=jsonexceptionout_of_range411>json.exception.out_of_range.411<a class=headerlink href=#jsonexceptionout_of_range411 title="Permanent link">&para;</a></h3> <p>A <abbr title="JavaScript Object Notation">JSON</abbr> Patch <code>add</code> operation cannot be applied because the target location's parent is neither an object nor an array. Per <a href="https://datatracker.ietf.org/doc/html/rfc6902"><abbr title="Request for Comments">RFC</abbr> 6902</a>, an <code>add</code> target must reference a member of an existing object or an element of an existing array; a primitive value (string, number, boolean, etc.) cannot receive a new member or element.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>cannot add value: the JSON Patch 'add' target's parent is of type string, but must be an object or array
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, this situation hit an internal assertion (aborting the program in debug builds) or was silently ignored when assertions were disabled.</p> <p>A <code>null</code> parent is rejected as well. Before version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>, an <code>add</code> into a <code>null</code> parent silently converted it to an object (e.g., <code>add</code> at <code>/foo/bar</code> turned <code>{"foo":null}</code> into <code>{"foo":{"bar":1}}</code>).</p> </div> <h3 id=jsonexceptionout_of_range412>json.exception.out_of_range.412<a class=headerlink href=#jsonexceptionout_of_range412 title="Permanent link">&para;</a></h3> <p><abbr title="Binary JSON">BSON</abbr> stores the length of documents, arrays, strings, and binary values in a signed 32-bit integer, and MessagePack stores the length of strings, binary values, arrays, and objects in at most an unsigned 32-bit integer. This exception is thrown when a value is too large to be described by such a length field.</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>BSON length 2147483661 exceeds maximum of 2147483647
</code></pre></div> <div class=highlight><pre><span></span><code>MessagePack length 4294967296 exceeds maximum of 4294967295
</code></pre></div></p> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, the <abbr title="Binary JSON">BSON</abbr> length was silently truncated, and <a href=../../api/basic_json/to_bson/ ><code>to_bson</code></a> produced documents with negative length prefixes that <a href=../../api/basic_json/from_bson/ ><code>from_bson</code></a> rejected; <a href=../../api/basic_json/to_msgpack/ ><code>to_msgpack</code></a> wrote such a value without any length, producing output that could not be read back.</p> </div> <h3 id=jsonexceptionout_of_range413>json.exception.out_of_range.413<a class=headerlink href=#jsonexceptionout_of_range413 title="Permanent link">&para;</a></h3> <p>A <abbr title="JavaScript Object Notation">JSON</abbr> Patch <code>remove</code> operation cannot be applied because the target location's parent is neither an object nor an array. Per <a href="https://datatracker.ietf.org/doc/html/rfc6902"><abbr title="Request for Comments">RFC</abbr> 6902</a>, a <code>remove</code> target must reference a member of an existing object or an element of an existing array; a primitive value (string, number, boolean, etc.) or <code>null</code> has no members or elements to remove.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>cannot remove value: the JSON Patch 'remove' target's parent is of type number, but must be an object or array
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, this situation was silently ignored (the <code>remove</code> operation had no effect).</p> </div> <h3 id=jsonexceptionout_of_range414>json.exception.out_of_range.414<a class=headerlink href=#jsonexceptionout_of_range414 title="Permanent link">&para;</a></h3> <p>A <abbr title="JavaScript Object Notation">JSON</abbr> Patch <code>move</code> operation's <code>"from"</code> location is a proper prefix of its <code>"path"</code> location. Per <a href="https://datatracker.ietf.org/doc/html/rfc6902"><abbr title="Request for Comments">RFC</abbr> 6902</a> (section 4.4), a location cannot be moved into one of its own children.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>cannot move value: 'from' path '/0' is a proper prefix of 'path' '/0/0'
</code></pre></div></p> </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 <abbr title="Binary JSON">BSON</abbr> 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>[json.exception.out_of_range.409] BSON key cannot contain code point U+0000 (at byte 2)
</code></pre></div> </div> <h3 id=jsonexceptionout_of_range410>json.exception.out_of_range.410<a class=headerlink href=#jsonexceptionout_of_range410 title="Permanent link">&para;</a></h3> <p>This exception is thrown when an undefined value is used with <a href=../../api/macros/nlohmann_json_serialize_enum_strict/ ><code>NLOHMANN_JSON_SERIALIZE_ENUM_STRICT</code></a>, or when an array index in a <abbr title="JavaScript Object Notation">JSON</abbr> pointer exceeds the range of <code>size_type</code> (e.g., on 32-bit platforms).</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.410] enum value out of range
[json.exception.out_of_range.410] array index 18446744073709551615 exceeds size_type
</code></pre></div> <p>The second message is thrown, for instance, by <code class=highlight><span class=n>json</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=s>"[1, 2]"</span><span class=p>).</span><span class=n>at</span><span class=p>(</span><span class=s>"/18446744073709551615"</span><span class=n>_json_pointer</span><span class=p>)</span></code> on a 64-bit platform, where <code>size_type</code> is <code class=highlight><span class=n>std</span><span class=o>::</span><span class=kt>size_t</span></code> and this index is <code>SIZE_MAX</code>. An index that does not fit into 64 bits (such as <code>18446744073709551616</code>) is not reported as 410 but as <a href=#jsonexceptionout_of_range404><code>out_of_range.404</code></a>.</p> </div> <h3 id=jsonexceptionout_of_range411>json.exception.out_of_range.411<a class=headerlink href=#jsonexceptionout_of_range411 title="Permanent link">&para;</a></h3> <p>A <abbr title="JavaScript Object Notation">JSON</abbr> Patch <code>add</code> operation cannot be applied because the target location's parent is neither an object nor an array. Per <a href="https://datatracker.ietf.org/doc/html/rfc6902"><abbr title="Request for Comments">RFC</abbr> 6902</a>, an <code>add</code> target must reference a member of an existing object or an element of an existing array; a primitive value (string, number, boolean, etc.) cannot receive a new member or element.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.411] cannot add value: the JSON Patch 'add' target's parent is of type string, but must be an object or array
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, this situation hit an internal assertion (aborting the program in debug builds) or was silently ignored when assertions were disabled.</p> <p>A <code>null</code> parent is rejected as well. Before version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>, an <code>add</code> into a <code>null</code> parent silently converted it to an object (e.g., <code>add</code> at <code>/foo/bar</code> turned <code>{"foo":null}</code> into <code>{"foo":{"bar":1}}</code>).</p> </div> <h3 id=jsonexceptionout_of_range412>json.exception.out_of_range.412<a class=headerlink href=#jsonexceptionout_of_range412 title="Permanent link">&para;</a></h3> <p><abbr title="Binary JSON">BSON</abbr> stores the length of documents, arrays, strings, and binary values in a signed 32-bit integer, and MessagePack stores the length of strings, binary values, arrays, and objects in at most an unsigned 32-bit integer. This exception is thrown when a value is too large to be described by such a length field.</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>[json.exception.out_of_range.412] BSON length 2147483661 exceeds maximum of 2147483647
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.412] MessagePack length 4294967296 exceeds maximum of 4294967295
</code></pre></div></p> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, the <abbr title="Binary JSON">BSON</abbr> length was silently truncated, and <a href=../../api/basic_json/to_bson/ ><code>to_bson</code></a> produced documents with negative length prefixes that <a href=../../api/basic_json/from_bson/ ><code>from_bson</code></a> rejected; <a href=../../api/basic_json/to_msgpack/ ><code>to_msgpack</code></a> wrote such a value without any length, producing output that could not be read back.</p> </div> <h3 id=jsonexceptionout_of_range413>json.exception.out_of_range.413<a class=headerlink href=#jsonexceptionout_of_range413 title="Permanent link">&para;</a></h3> <p>A <abbr title="JavaScript Object Notation">JSON</abbr> Patch <code>remove</code> operation cannot be applied because the target location's parent is neither an object nor an array. Per <a href="https://datatracker.ietf.org/doc/html/rfc6902"><abbr title="Request for Comments">RFC</abbr> 6902</a>, a <code>remove</code> target must reference a member of an existing object or an element of an existing array; a primitive value (string, number, boolean, etc.) or <code>null</code> has no members or elements to remove.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.413] cannot remove value: the JSON Patch 'remove' target's parent is of type number, but must be an object or array
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, this situation was silently ignored (the <code>remove</code> operation had no effect).</p> </div> <h3 id=jsonexceptionout_of_range414>json.exception.out_of_range.414<a class=headerlink href=#jsonexceptionout_of_range414 title="Permanent link">&para;</a></h3> <p>A <abbr title="JavaScript Object Notation">JSON</abbr> Patch <code>move</code> operation's <code>"from"</code> location is a proper prefix of its <code>"path"</code> location. Per <a href="https://datatracker.ietf.org/doc/html/rfc6902"><abbr title="Request for Comments">RFC</abbr> 6902</a> (section 4.4), a location cannot be moved into one of its own children.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.414] cannot move value: 'from' path '/0' is a proper prefix of 'path' '/0/0'
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, this situation could succeed with a corrupted result: for an array target, removing the "from" element before the "add" step shifted subsequent indices, so "path" silently re-resolved to a different element than intended.</p> </div> <h3 id=jsonexceptionout_of_range415>json.exception.out_of_range.415<a class=headerlink href=#jsonexceptionout_of_range415 title="Permanent link">&para;</a></h3> <p>MessagePack's ext type and <abbr title="Binary JSON">BSON</abbr>'s binary subtype are each stored in a single byte. This exception is thrown when serializing a <a href=../../api/byte_container_with_subtype/ ><code>byte_container_with_subtype</code></a> whose subtype exceeds 255, the largest value the library can store in that byte.</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.415] subtype 70000 is too large for the MessagePack ext type (max 255)
</code></pre></div> <div class=highlight><pre><span></span><code>[json.exception.out_of_range.415] subtype 70000 is too large for the BSON binary subtype (max 255)
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, subtypes above 255 were silently truncated modulo 256 instead of raising an error.</p> </div> <h3 id=jsonexceptionout_of_range416>json.exception.out_of_range.416<a class=headerlink href=#jsonexceptionout_of_range416 title="Permanent link">&para;</a></h3> <p><a href=../../api/basic_json_document/parse/ ><code>basic_json_document::parse()</code></a> and the other parsing functions of <a href=../../api/basic_json_document/ ><code>basic_json_document</code></a> index a value's position in the source text in 32 bits, so they do not support an input of 4294967280 bytes (4 <abbr title="Gibibyte (2^30 bytes)">GiB</abbr> minus 16 bytes) or more. The same 32-bit limit applies to an <strong>editable</strong> document's own storage: <a href=../../api/basic_json_document/set/ ><code>set</code></a> and <a href=../../api/basic_json_document/push_back/ ><code>push_back</code></a> throw this exception once the strings and number tokens written by edits reach 4 <abbr title="Gibibyte (2^30 bytes)">GiB</abbr> in total, or once more than 4294967295 arrays/objects have had an element set or appended to them. The same limit applies to an <a href=../../features/json_view/#images>image</a>: <a href=../../api/basic_json_document/save/ ><code>save()</code></a> throws it if the node count, the text, or the decoded strings it would write would individually reach 4 <abbr title="Gibibyte (2^30 bytes)">GiB</abbr>.</p> <div class="admonition failure"> <p class=admonition-title>Example messages</p> <p><div class=highlight><pre><span></span><code>[json.exception.out_of_range.416] input of 4294967280 bytes or more is not supported by json_document
@@ -318,4 +306,4 @@ array index 18446744073709551615 exceeds size_type
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 <abbr title="JavaScript Object Notation">JSON</abbr> 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>"op"</span><span class=p>:</span><span class=s2>"test"</span><span class=p>,</span><span class=w> </span><span class=nt>"path"</span><span class=p>:</span><span class=s2>"/baz"</span><span class=p>,</span><span class=w> </span><span class=nt>"value"</span><span class=p>:</span><span class=s2>"bar"</span><span class=p>}</span></code> on <code class=highlight><span class=p>{</span><span class=nt>"baz"</span><span class=p>:</span><span class=w> </span><span class=s2>"qux"</span><span class=p>}</span></code>:</p> <div class=highlight><pre><span></span><code>[json.exception.other_error.501] unsuccessful: {"op":"test","path":"/baz","value":"bar"}
</code></pre></div> </div> <h3 id=jsonexceptionother_error502>json.exception.other_error.502<a class=headerlink href=#jsonexceptionother_error502 title="Permanent link">&para;</a></h3> <p><a href=../../api/basic_json/to_ubjson/ ><code>to_ubjson</code></a> and <a href=../../api/basic_json/to_bjdata/ ><code>to_bjdata</code></a> were called with <code>use_type = true</code> but <code>use_size = false</code>, and the value contains a non-empty array or object (or, with <abbr title="Binary JData">BJData</abbr> Draft 3, any binary value). <abbr title="Universal Binary JSON">UBJSON</abbr> requires a size marker (<code>#</code>) after a type marker (<code>$</code>); scalars and empty arrays or objects do not throw.</p> <div class="admonition failure"> <p class=admonition-title>Example message</p> <div class=highlight><pre><span></span><code>[json.exception.other_error.502] use_type requires use_size = true
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added in version 3.13.0 <span class=unreleased-version title="Not part of a release yet; the latest release is 3.12.0.">unreleased</span>. Before that, debug builds aborted on an assertion and release builds wrote a <code>$</code> marker without <code>#</code>, which <a href=../../api/basic_json/from_ubjson/ ><code>from_ubjson</code></a> then rejected.</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 26, 2026 19:13:30 UTC">October 26, 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 of labels.getElementsByTagName("label"))if(label.innerText.trim()===tab){var input=document.getElementById(label.htmlFor);input.checked=!0;continue e}}</script> <script>var target=document.getElementById(location.hash.slice(1));target&&target.name&&(target.checked=target.name.startsWith("__tabbed_"))</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 8z"/></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; 2013-2026 Niels Lohmann </div> </div> <div class=md-social> <a href="https://github.com/nlohmann" target="_blank" rel="noopener" title="github.com" class="md-social__link"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 512 512"><!-- Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2025 Fonticons, Inc.--><path d="M173.9 397.4c0 2-2.3 3.6-5.2 3.6-3.3.3-5.6-1.3-5.6-3.6 0-2 2.3-3.6 5.2-3.6 3-.3 5.6 1.3 5.6 3.6m-31.1-4.5c-.7 2 1.3 4.3 4.3 4.9 2.6 1 5.6 0 6.2-2s-1.3-4.3-4.3-5.2c-2.6-.7-5.5.3-6.2 2.3m44.2-1.7c-2.9.7-4.9 2.6-4.6 4.9.3 2 2.9 3.3 5.9 2.6 2.9-.7 4.9-2.6 4.6-4.6-.3-1.9-3-3.2-5.9-2.9M252.8 8C114.1 8 8 113.3 8 252c0 110.9 69.8 205.8 169.5 239.2 12.8 2.3 17.3-5.6 17.3-12.1 0-6.2-.3-40.4-.3-61.4 0 0-70 15-84.7-29.8 0 0-11.4-29.1-27.8-36.6 0 0-22.9-15.7 1.6-15.4 0 0 24.9 2 38.6 25.8 21.9 38.6 58.6 27.5 72.9 20.9 2.3-16 8.8-27.1 16-33.7-55.9-6.2-112.3-14.3-112.3-110.5 0-27.5 7.6-41.3 23.6-58.9-2.6-6.5-11.1-33.3 2.6-67.9 20.9-6.5 69 27 69 27 20-5.6 41.5-8.5 62.8-8.5s42.8 2.9 62.8 8.5c0 0 48.1-33.6 69-27 13.7 34.7 5.2 61.4 2.6 67.9 16 17.7 25.8 31.5 25.8 58.9 0 96.5-58.9 104.2-114.8 110.5 9.2 7.9 17 22.9 17 46.4 0 33.7-.3 75.4-.3 83.6 0 6.5 4.6 14.4 17.3 12.1C436.2 457.8 504 362.9 504 252 504 113.3 391.5 8 252.8 8M105.2 352.9c-1.3 1-1 3.3.7 5.2 1.6 1.6 3.9 2.3 5.2 1 1.3-1 1-3.3-.7-5.2-1.6-1.6-3.9-2.3-5.2-1m-10.8-8.1c-.7 1.3.3 2.9 2.3 3.9 1.6 1 3.6.7 4.3-.7.7-1.3-.3-2.9-2.3-3.9-2-.6-3.6-.3-4.3.7m32.4 35.6c-1.6 1.3-1 4.3 1.3 6.2 2.3 2.3 5.2 2.6 6.5 1 1.3-1.3.7-4.3-1.3-6.2-2.2-2.3-5.2-2.6-6.5-1m-11.4-14.7c-1.6 1-1.6 3.6 0 5.9s4.3 3.3 5.6 2.3c1.6-1.3 1.6-3.9 0-6.2-1.4-2.3-4-3.3-5.6-2"/></svg> </a> <a href="https://www.linkedin.com/in/nielslohmann/" target="_blank" rel="noopener" title="www.linkedin.com" class="md-social__link"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 448 512"><!-- Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2025 Fonticons, Inc.--><path d="M416 32H31.9C14.3 32 0 46.5 0 64.3v383.4C0 465.5 14.3 480 31.9 480H416c17.6 0 32-14.5 32-32.3V64.3c0-17.8-14.4-32.3-32-32.3M135.4 416H69V202.2h66.5V416zM102.2 96a38.5 38.5 0 1 1 0 77 38.5 38.5 0 1 1 0-77m282.1 320h-66.4V312c0-24.8-.5-56.7-34.5-56.7-34.6 0-39.9 27-39.9 54.9V416h-66.4V202.2h63.7v29.2h.9c8.9-16.8 30.6-34.5 62.9-34.5 67.2 0 79.7 44.3 79.7 101.9z"/></svg> </a> <a href="https://www.xing.com/profile/Niels_Lohmann" target="_blank" rel="noopener" title="www.xing.com" class="md-social__link"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 384 512"><!-- Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.Line truncated
</code></pre></div> </div> <div class="admonition note"> <p class=admonition-title>Note</p> <p>This exception was added 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>. Before that, debug builds aborted on an assertion and release builds wrote a <code>$</code> marker without <code>#</code>, which <a href=../../api/basic_json/from_ubjson/ ><code>from_ubjson</code></a> then rejected.</p> </div> <h2 id=see-also>See also<a class=headerlink href=#see-also title="Permanent link">&para;</a></h2> <ul> <li><a href=../../api/basic_json/exception/ ><code>exception</code></a> - base class of all exceptions thrown by the library</li> <li><a href=../../api/basic_json/parse_error/ ><code>parse_error</code></a> - exceptions indicating a parse error</li> <li><a href=../../api/basic_json/invalid_iterator/ ><code>invalid_iterator</code></a> - exceptions indicating errors with iterators</li> <li><a href=../../api/basic_json/type_error/ ><code>type_error</code></a> - exceptions indicating a wrong type</li> <li><a href=../../api/basic_json/out_of_range/ ><code>out_of_range</code></a> - exceptions indicating access out of range</li> <li><a href=../../api/basic_json/other_error/ ><code>other_error</code></a> - exceptions indicating other library errors</li> <li><a href=../../api/macros/json_noexception/ ><code>JSON_NOEXCEPTION</code></a> - switch off exceptions</li> <li><a href=../../api/macros/json_diagnostics/ ><code>JSON_DIAGNOSTICS</code></a> - extended exception messages with the path of the failing value</li> <li><a href=../../features/no_exceptions/ >Working Without Exceptions</a> - use the library without exceptions</li> </ul> <!-- 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 27, 2026 06:41:42 UTC">October 27, 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 of labels.getElementsByTagName("label"))if(label.innerText.trim()===tab){var input=document.getElementById(label.htmlFor);input.checked=!0;continue e}}</script> <script>var target=document.getElementById(location.hash.slice(1));target&&target.name&&(target.checked=target.name.startsWith("__tabbed_"))</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 8z"/></svg> Back to top </button> </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"> <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 11z"/></svg> </div> <div class=md-footer__title> <span class=md-footer__direction> Previous </span> <div class=md-ellipsis> FAQ </div> </div> </a> <a href=../releases/ class="md-footer__link md-footer__link--next" aria-label="Next: Overview"> <div class=md-footer__title> <span class=md-footer__direction> Next </span> <div class=md-ellipsis> Overview </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 11z"/></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; 2013-2026 Niels Lohmann </div> </div> <div class=md-social> <a href="https://github.com/nlohmann" target="_blank" rel="noopener" title="github.com" class="md-social__link"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 512 512"><!-- Font Awesome Free 7.1.0 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2025 Fonticons, Inc.--><path d="M173.9 397.4c0 2-2.3 3.6-5.2 3.6-3.3.3-5.6-1.3-5.6-3.6 0-2 2.3-3.6 5.2-3.6 3-.3 5.6 1.3 5.6 3.6m-31.1-4.5c-.7 2 1.3 4.3 4.3 4.9 2.6 1 5.6 0 6.2-2s-1.3-4.3-4.3-5.2c-2.6-.7-5.5.3-6.2 2.3m44.2-1.7c-2.9.7-4.9 2.6-4.6 4.9.3 2 2.9 Line truncated