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<!doctype html><html lang=en class=no-js> <head><meta charset=utf-8><meta name=viewport content="width=device-width,initial-scale=1"><meta name=author content="Niels Lohmann"><link href="https://json.nlohmann.me/api/basic_json_view/operator_ne/" rel="canonical"><link href=../operator_eq/ rel=prev><link href=../size/ rel=next><link rel=icon href=../../../assets/images/favicon.png><meta name=generator content="mkdocs-1.6.1, mkdocs-material-9.7.7"><title>operator!= - JSON for Modern C++</title><link rel=stylesheet href=../../../assets/stylesheets/main.ec1eaa64.min.css><link rel=stylesheet href=../../../assets/stylesheets/palette.ab4e12ef.min.css><link rel="stylesheet" href="../../../assets/external/fonts.googleapis.com/css.61a430c9.css"><style>:root{--md-text-font:"Roboto";--md-code-font:"JetBrains Mono"}</style><link rel=stylesheet href=../../../css/custom.css><script>__md_scope=new 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<span class=kt>bool</span><span class=w> </span><span class=k>operator</span><span class=o>!=</span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>basic_json_view</span><span class=o>&</span><span class=w> </span><span class=n>lhs</span><span class=p>,</span><span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>basic_json_view</span><span class=o>&</span><span class=w> </span><span class=n>rhs</span><span class=p>);</span>
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<span class=c1>// (2)</span>
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<span class=kt>bool</span><span class=w> </span><span class=k>operator</span><span class=o>!=</span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>basic_json_view</span><span class=o>&</span><span class=w> </span><span class=n>lhs</span><span class=p>,</span><span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>BasicJsonType</span><span class=o>&</span><span class=w> </span><span class=n>rhs</span><span class=p>);</span>
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<span class=kt>bool</span><span class=w> </span><span class=k>operator</span><span class=o>!=</span><span class=p>(</span><span class=k>const</span><span class=w> </span><span class=n>BasicJsonType</span><span class=o>&</span><span class=w> </span><span class=n>lhs</span><span class=p>,</span><span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>basic_json_view</span><span class=o>&</span><span class=w> </span><span class=n>rhs</span><span class=p>);</span>
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</code></pre></div> <ol> <li>Compares two views for inequality. Returns <code class=highlight><span class=o>!</span><span class=p>(</span><span class=n>lhs</span><span class=w> </span><span class=o>==</span><span class=w> </span><span class=n>rhs</span><span class=p>)</span></code>, see <a href=../operator_eq/ >operator==</a>.</li> <li>Compares a view and a <code>BasicJsonType</code> value for inequality, in either order. Returns <code class=highlight><span class=o>!</span><span class=p>(</span><span class=n>lhs</span><span class=w> </span><span class=o>==</span><span class=w> </span><span class=n>rhs</span><span class=p>)</span></code> (or, for the reversed order, <code class=highlight><span class=o>!</span><span class=p>(</span><span class=n>rhs</span><span class=w> </span><span class=o>==</span><span class=w> </span><span class=n>lhs</span><span class=p>)</span></code>), see <a href=../operator_eq/ >operator==</a>.</li> </ol> <p>Since <code>operator!=</code> is defined as the negation of <a href=../operator_eq/ ><code>operator==</code></a>, it follows the same rules for special cases: for instance, since a <a href=../is_discarded/ >discarded</a> view is never equal to anything by default (see <a href=../operator_eq/#notes>operator=='s Notes</a>), it is never <em>unequal</em> to anything either -- <code class=highlight><span class=n>discarded</span><span class=w> </span><span class=o>!=</span><span class=w> </span><span class=n>discarded</span></code> is also <code class=highlight><span class=nb>false</span></code>, exactly as for a discarded <code>BasicJsonType</code> value.</p> <h2 id=parameters>Parameters<a class=headerlink href=#parameters title="Permanent link">¶</a></h2> <dl> <dt><code>lhs</code> (in)</dt> <dd>first value to consider</dd> <dt><code>rhs</code> (in)</dt> <dd>second value to consider</dd> </dl> <h2 id=return-value>Return value<a class=headerlink href=#return-value title="Permanent link">¶</a></h2> <p>whether the values <code>lhs</code> and <code>rhs</code> are not equal</p> <h2 id=exception-safety>Exception safety<a class=headerlink href=#exception-safety title="Permanent link">¶</a></h2> <p>Strong exception safety: if an exception is thrown, there are no changes to either operand, or to the document(s) a view refers to.</p> <h2 id=exceptions>Exceptions<a class=headerlink href=#exceptions title="Permanent link">¶</a></h2> <p>May throw <code class=highlight><span class=n>std</span><span class=o>::</span><span class=n>bad_alloc</span></code>, propagated from <a href=../operator_eq/#exceptions><code>operator==</code></a>. Unlike most other <code>basic_json_view</code> functions, <code>operator!=</code> is not <code class=highlight><span class=k>noexcept</span></code>.</p> <h2 id=complexity>Complexity<a class=headerlink href=#complexity title="Permanent link">¶</a></h2> <p>Linear, as <a href=../operator_eq/#complexity><code>operator==</code></a>.</p> <h2 id=notes>Notes<a class=headerlink href=#notes title="Permanent link">¶</a></h2> <p>See the <a href=../operator_eq/#notes>Notes</a> of <code>operator==</code> -- in particular for how an object's members are compared (order matters for <a href=../../ordered_json_view/ ><code>ordered_json_view</code></a> but not for <a href=../../json_view/ ><code>json_view</code></a>) and for how discarded views compare.</p> <p>No ordering comparison (<code class=highlight><span class=k>operator</span><span class=o><</span></code>) is provided for <code>basic_json_view</code>; <a href=../materialize/ ><code>materialize()</code></a> is the way to get a <code>BasicJsonType</code> value that supports it.</p> <h2 id=examples>Examples<a class=headerlink href=#examples title="Permanent link">¶</a></h2> <details class=example> <summary>Example</summary> <p>The example below asserts, as a test would, that a received document differs from an unwanted value, and shows that -- as for <a href=../../json/ ><code>json</code></a>/<a href=../../ordered_json/ ><code>ordered_json</code></a> -- reordering an object's members is detected as a difference for an <code>ordered_json_view</code> but not for a <code>json_view</code>.</p> <div class=highlight><pre><span></span><code><span class=cp>#include</span><span class=w> </span><span class=cpf><iostream></span>
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<span class=cp>#include</span><span class=w> </span><span class=cpf><nlohmann/json_view.hpp></span>
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<span class=k>using</span><span class=w> </span><span class=n>json_document</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_document</span><span class=p>;</span>
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<span class=k>using</span><span class=w> </span><span class=n>ordered_json_document</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>ordered_json_document</span><span class=p>;</span>
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<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>
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<span class=kt>int</span><span class=w> </span><span class=nf>main</span><span class=p>()</span>
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<span class=p>{</span>
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<span class=w> </span><span class=c1>// assert, as a test would, that a received document differs from an</span>
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<span class=w> </span><span class=c1>// unwanted shape -- without ever materializing it into a json value just</span>
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<span class=w> </span><span class=c1>// to compare</span>
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<span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>json_document</span><span class=w> </span><span class=n>received</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>json_document</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span>
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<span class=w> </span><span class=sa>R</span><span class=s>"</span><span class=dl>(</span><span class=s>{"status": "ok", "code": 200}</span><span class=dl>)</span><span class=s>"</span><span class=p>);</span>
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<span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>json</span><span class=w> </span><span class=n>unwanted</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=p>{{</span><span class=s>"status"</span><span class=p>,</span><span class=w> </span><span class=s>"error"</span><span class=p>},</span><span class=w> </span><span class=p>{</span><span class=s>"code"</span><span class=p>,</span><span class=w> </span><span class=mi>500</span><span class=p>}};</span>
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<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><<</span><span class=w> </span><span class=n>std</span><span class=o>::</span><span class=n>boolalpha</span><span class=w> </span><span class=o><<</span><span class=w> </span><span class=p>(</span><span class=n>received</span><span class=p>.</span><span class=n>root</span><span class=p>()</span><span class=w> </span><span class=o>!=</span><span class=w> </span><span class=n>unwanted</span><span class=p>)</span><span class=w> </span><span class=o><<</span><span class=w> </span><span class=sc>'\n'</span><span class=p>;</span>
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<span class=w> </span><span class=c1>// json (std::map) compares object members regardless of order ...</span>
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<span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>json_document</span><span class=w> </span><span class=n>a</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>json_document</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=sa>R</span><span class=s>"</span><span class=dl>(</span><span class=s>{"a": 1, "b": 2}</span><span class=dl>)</span><span class=s>"</span><span class=p>);</span>
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<span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>json_document</span><span class=w> </span><span class=n>b</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>json_document</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=sa>R</span><span class=s>"</span><span class=dl>(</span><span class=s>{"b": 2, "a": 1}</span><span class=dl>)</span><span class=s>"</span><span class=p>);</span>
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<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><<</span><span class=w> </span><span class=p>(</span><span class=n>a</span><span class=p>.</span><span class=n>root</span><span class=p>()</span><span class=w> </span><span class=o>!=</span><span class=w> </span><span class=n>b</span><span class=p>.</span><span class=n>root</span><span class=p>())</span><span class=w> </span><span class=o><<</span><span class=w> </span><span class=sc>'\n'</span><span class=p>;</span>
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<span class=w> </span><span class=c1>// ... but ordered_json (ordered_map) compares them in the order they</span>
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<span class=w> </span><span class=c1>// appear, so the very same reordering is detected as a difference</span>
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<span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>ordered_json_document</span><span class=w> </span><span class=n>oa</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>ordered_json_document</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=sa>R</span><span class=s>"</span><span class=dl>(</span><span class=s>{"a": 1, "b": 2}</span><span class=dl>)</span><span class=s>"</span><span class=p>);</span>
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<span class=w> </span><span class=k>const</span><span class=w> </span><span class=n>ordered_json_document</span><span class=w> </span><span class=n>ob</span><span class=w> </span><span class=o>=</span><span class=w> </span><span class=n>ordered_json_document</span><span class=o>::</span><span class=n>parse</span><span class=p>(</span><span class=sa>R</span><span class=s>"</span><span class=dl>(</span><span class=s>{"b": 2, "a": 1}</span><span class=dl>)</span><span class=s>"</span><span class=p>);</span>
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<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><<</span><span class=w> </span><span class=p>(</span><span class=n>oa</span><span class=p>.</span><span class=n>root</span><span class=p>()</span><span class=w> </span><span class=o>!=</span><span class=w> </span><span class=n>ob</span><span class=p>.</span><span class=n>root</span><span class=p>())</span><span class=w> </span><span class=o><<</span><span class=w> </span><span class=sc>'\n'</span><span class=p>;</span>
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<span class=p>}</span>
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</code></pre></div> <p>Output:</p> <div class=highlight><pre><span></span><code><span class=kc>true</span>
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<span class=kc>false</span>
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<span class=kc>true</span>
|
||||
</code></pre></div> </details> <h2 id=see-also>See also<a class=headerlink href=#see-also title="Permanent link">¶</a></h2> <ul> <li><a href=../operator_eq/ >operator==</a> - compare for equality</li> <li><a href=../materialize/ >materialize</a> - build a <code>BasicJsonType</code> value, e.g. to keep comparing after the document is gone</li> <li><a href=../../basic_json/operator_ne/ ><code>BasicJsonType::operator!=</code></a> - the corresponding function of <code>basic_json</code></li> </ul> <h2 id=version-history>Version history<a class=headerlink href=#version-history title="Permanent link">¶</a></h2> <ul> <li>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>.</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 21, 2026 08:21:28 UTC">October 21, 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 © 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 62.9-34.5Line truncated
|
||||
@@ -0,0 +1,98 @@
|
||||
# nlohmann::basic_json_view::operator!=
|
||||
|
||||
```
|
||||
// (1)
|
||||
bool operator!=(const basic_json_view& lhs, const basic_json_view& rhs);
|
||||
|
||||
// (2)
|
||||
bool operator!=(const basic_json_view& lhs, const BasicJsonType& rhs);
|
||||
bool operator!=(const BasicJsonType& lhs, const basic_json_view& rhs);
|
||||
```
|
||||
|
||||
1. Compares two views for inequality. Returns `!(lhs == rhs)`, see [operator==](https://json.nlohmann.me/api/basic_json_view/operator_eq/index.md).
|
||||
1. Compares a view and a `BasicJsonType` value for inequality, in either order. Returns `!(lhs == rhs)` (or, for the reversed order, `!(rhs == lhs)`), see [operator==](https://json.nlohmann.me/api/basic_json_view/operator_eq/index.md).
|
||||
|
||||
Since `operator!=` is defined as the negation of [`operator==`](https://json.nlohmann.me/api/basic_json_view/operator_eq/index.md), it follows the same rules for special cases: for instance, since a [discarded](https://json.nlohmann.me/api/basic_json_view/is_discarded/index.md) view is never equal to anything by default (see [operator=='s Notes](https://json.nlohmann.me/api/basic_json_view/operator_eq/#notes)), it is never *unequal* to anything either -- `discarded != discarded` is also `false`, exactly as for a discarded `BasicJsonType` value.
|
||||
|
||||
## Parameters
|
||||
|
||||
`lhs` (in) : first value to consider
|
||||
|
||||
`rhs` (in) : second value to consider
|
||||
|
||||
## Return value
|
||||
|
||||
whether the values `lhs` and `rhs` are not equal
|
||||
|
||||
## Exception safety
|
||||
|
||||
Strong exception safety: if an exception is thrown, there are no changes to either operand, or to the document(s) a view refers to.
|
||||
|
||||
## Exceptions
|
||||
|
||||
May throw `std::bad_alloc`, propagated from [`operator==`](https://json.nlohmann.me/api/basic_json_view/operator_eq/#exceptions). Unlike most other `basic_json_view` functions, `operator!=` is not `noexcept`.
|
||||
|
||||
## Complexity
|
||||
|
||||
Linear, as [`operator==`](https://json.nlohmann.me/api/basic_json_view/operator_eq/#complexity).
|
||||
|
||||
## Notes
|
||||
|
||||
See the [Notes](https://json.nlohmann.me/api/basic_json_view/operator_eq/#notes) of `operator==` -- in particular for how an object's members are compared (order matters for [`ordered_json_view`](https://json.nlohmann.me/api/ordered_json_view/index.md) but not for [`json_view`](https://json.nlohmann.me/api/json_view/index.md)) and for how discarded views compare.
|
||||
|
||||
No ordering comparison (`operator<`) is provided for `basic_json_view`; [`materialize()`](https://json.nlohmann.me/api/basic_json_view/materialize/index.md) is the way to get a `BasicJsonType` value that supports it.
|
||||
|
||||
## Examples
|
||||
|
||||
Example
|
||||
|
||||
The example below asserts, as a test would, that a received document differs from an unwanted value, and shows that -- as for [`json`](https://json.nlohmann.me/api/json/index.md)/[`ordered_json`](https://json.nlohmann.me/api/ordered_json/index.md) -- reordering an object's members is detected as a difference for an `ordered_json_view` but not for a `json_view`.
|
||||
|
||||
```
|
||||
#include <iostream>
|
||||
#include <nlohmann/json_view.hpp>
|
||||
|
||||
using json_document = nlohmann::json_document;
|
||||
using ordered_json_document = nlohmann::ordered_json_document;
|
||||
using json = nlohmann::json;
|
||||
|
||||
int main()
|
||||
{
|
||||
// assert, as a test would, that a received document differs from an
|
||||
// unwanted shape -- without ever materializing it into a json value just
|
||||
// to compare
|
||||
const json_document received = json_document::parse(
|
||||
R"({"status": "ok", "code": 200})");
|
||||
const json unwanted = {{"status", "error"}, {"code", 500}};
|
||||
std::cout << std::boolalpha << (received.root() != unwanted) << '\n';
|
||||
|
||||
// json (std::map) compares object members regardless of order ...
|
||||
const json_document a = json_document::parse(R"({"a": 1, "b": 2})");
|
||||
const json_document b = json_document::parse(R"({"b": 2, "a": 1})");
|
||||
std::cout << (a.root() != b.root()) << '\n';
|
||||
|
||||
// ... but ordered_json (ordered_map) compares them in the order they
|
||||
// appear, so the very same reordering is detected as a difference
|
||||
const ordered_json_document oa = ordered_json_document::parse(R"({"a": 1, "b": 2})");
|
||||
const ordered_json_document ob = ordered_json_document::parse(R"({"b": 2, "a": 1})");
|
||||
std::cout << (oa.root() != ob.root()) << '\n';
|
||||
}
|
||||
```
|
||||
|
||||
Output:
|
||||
|
||||
```
|
||||
true
|
||||
false
|
||||
true
|
||||
```
|
||||
|
||||
## See also
|
||||
|
||||
- [operator==](https://json.nlohmann.me/api/basic_json_view/operator_eq/index.md) - compare for equality
|
||||
- [materialize](https://json.nlohmann.me/api/basic_json_view/materialize/index.md) - build a `BasicJsonType` value, e.g. to keep comparing after the document is gone
|
||||
- [`BasicJsonType::operator!=`](https://json.nlohmann.me/api/basic_json/operator_ne/index.md) - the corresponding function of `basic_json`
|
||||
|
||||
## Version history
|
||||
|
||||
- Added in version 3.13.0 unreleased.
|
||||
Reference in new issue
Block a user