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data-v-a3c25e27 data-v-cb998dce><!--[--><!--]--><!--[--><!--]--><div class="VPDocAsideOutline" role="navigation" data-v-cb998dce data-v-3a6c4994><div class="content" data-v-3a6c4994><div class="outline-marker" data-v-3a6c4994></div><div class="outline-title" role="heading" aria-level="2" data-v-3a6c4994>On this page</div><nav aria-labelledby="doc-outline-aria-label" data-v-3a6c4994><span class="visually-hidden" id="doc-outline-aria-label" data-v-3a6c4994> Table of Contents for current page </span><ul class="root" data-v-3a6c4994 data-v-463da30f><!--[--><!--]--></ul></nav></div></div><!--[--><!--]--><div class="spacer" data-v-cb998dce></div><!--[--><!--]--><!----><!--[--><!--]--><!--[--><!--]--></div></div></div></div><div class="content" data-v-a3c25e27><div class="content-container" data-v-a3c25e27><!--[--><!--]--><!----><main class="main" data-v-a3c25e27><div style="position:relative;" class="vp-doc _terminology" data-v-a3c25e27><div><h1 id="terminology" tabindex="-1">Terminology <a class="header-anchor" href="#terminology" aria-label="Permalink to &quot;Terminology&quot;">​</a></h1><p>In this section, we are going to explain the basic terminology.</p><h2 id="rule" tabindex="-1">Rule <a class="header-anchor" href="#rule" aria-label="Permalink to &quot;Rule&quot;">​</a></h2><p>A rule is a function that takes at least one argument (value) and validates the data. It should return a <code>true</code> or <code>false</code> value as a return.</p><p>The following type definition is the definition of a rule function.</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">type</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> RuleFunction</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> (</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">...</span><span style="--shiki-light:#E36209;--shiki-dark:#FFAB70;">args</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">:</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> any</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">[]) </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=&gt;</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> Promise</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">&lt;</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">boolean</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">&gt; </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">|</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> boolean</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">;</span></span></code></pre></div><p>The first parameter of a rule function should be the value that will be validated always.</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> (</span><span style="--shiki-light:#E36209;--shiki-dark:#FFAB70;">value</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">:</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> any</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">:</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> boolean</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">  // Return `true` if the `value` is valid.</span></span>
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  return</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> true</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">;</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">};</span></span></code></pre></div><p>A rule function always might have more parameters if it needs them. For example, if you want to check the minimum string size, the rule function should have to parameter like the following example.</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">export</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> default</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> (</span><span style="--shiki-light:#E36209;--shiki-dark:#FFAB70;">value</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">:</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> any</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">, </span><span style="--shiki-light:#E36209;--shiki-dark:#FFAB70;">size</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">:</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> any</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">)</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">:</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> boolean</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">  // Return `true` if the `value` is valid.</span></span>
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">  return</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> true</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">;</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">};</span></span></code></pre></div><p>A rule should be able to execute directly.</p><div class="language-ts vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">ts</span><pre class="shiki shiki-themes github-light github-dark vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">import</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> { isRequired } </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">from</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;"> &quot;robust-validator&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">;</span></span>
<span class="line"></span>
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> result</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> isRequired</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;data&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">);</span></span></code></pre></div><div class="warning custom-block"><p class="custom-block-title">WARNING</p><p>Each rule function should validate only one thing. For example, the <code>email</code> validation <strong>should NOT</strong> check if the data is provided. Otherwise, a rule function can not check the optional data.</p><p>That&#39;s why <code>null</code> and <code>undefined</code> values are acceptable for all rules except the <code>required</code>.</p><p>If you want to check if the data is provided and is a valid email, you should use two rules (<code>required</code>, <code>email</code>) at the same time.</p></div><h2 id="definition" tabindex="-1">Definition <a class="header-anchor" href="#definition" aria-label="Permalink to &quot;Definition&quot;">​</a></h2><p>The definition means which rule sets will be executed for data.</p><p>It should be an object like the following example:</p><div class="language-js vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">js</span><pre class="shiki shiki-themes github-light github-dark vp-code"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> definition</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  email: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;required|email&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  name: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;required|min:1|max:50&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">  surname: </span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;required|min:1|max:50&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">,</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">};</span></span></code></pre></div><p>For each data property, the rule names should be defined.</p><p>The <code>|</code> should be used to be able to use multiple rule names at the same time:</p><p><code>required|email|alpha</code></p><p>All possible rule parameters should be defined after the <code>:</code> operator. If there is more than one parameter, they must be separated using commas.</p><p><code>required|min:1|max:50|between:1,50</code></p></div></div></main><footer class="VPDocFooter" data-v-a3c25e27 data-v-b4b63abf><!--[--><!--]--><div class="edit-info" data-v-b4b63abf><div class="edit-link" data-v-b4b63abf><a class="VPLink link vp-external-link-icon no-icon edit-link-button" href="https://github.com/axe-api/validator/edit/main/docs/terminology.md" target="_blank" rel="noreferrer" data-v-b4b63abf><!--[--><svg xmlns="http://www.w3.org/2000/svg" viewbox="0 0 24 24" class="edit-link-icon" aria-label="edit icon" data-v-b4b63abf><path d="M18,23H4c-1.7,0-3-1.3-3-3V6c0-1.7,1.3-3,3-3h7c0.6,0,1,0.4,1,1s-0.4,1-1,1H4C3.4,5,3,5.4,3,6v14c0,0.6,0.4,1,1,1h14c0.6,0,1-0.4,1-1v-7c0-0.6,0.4-1,1-1s1,0.4,1,1v7C21,21.7,19.7,23,18,23z"></path><path d="M8,17c-0.3,0-0.5-0.1-0.7-0.3C7,16.5,6.9,16.1,7,15.8l1-4c0-0.2,0.1-0.3,0.3-0.5l9.5-9.5c1.2-1.2,3.2-1.2,4.4,0c1.2,1.2,1.2,3.2,0,4.4l-9.5,9.5c-0.1,0.1-0.3,0.2-0.5,0.3l-4,1C8.2,17,8.1,17,8,17zM9.9,12.5l-0.5,2.1l2.1-0.5l9.3-9.3c0.4-0.4,0.4-1.1,0-1.6c-0.4-0.4-1.2-0.4-1.6,0l0,0L9.9,12.5z M18.5,2.5L18.5,2.5L18.5,2.5z"></path></svg> Edit this page on GitHub<!--]--></a></div><!----></div><nav class="prev-next" data-v-b4b63abf><div class="pager" data-v-b4b63abf><a class="VPLink link pager-link prev" href="/examples.html" data-v-b4b63abf><!--[--><span class="desc" data-v-b4b63abf>Previous page</span><span class="title" data-v-b4b63abf>Examples</span><!--]--></a></div><div class="pager" data-v-b4b63abf><a class="VPLink link pager-link next" href="/rules.html" data-v-b4b63abf><!--[--><span class="desc" data-v-b4b63abf>Next page</span><span class="title" data-v-b4b63abf>Rules</span><!--]--></a></div></nav></footer><!--[--><!--]--></div></div></div><!--[--><!--]--></div></div><footer class="VPFooter has-sidebar" data-v-9d8abc1e data-v-566314d4><div class="container" data-v-566314d4><p class="message" data-v-566314d4>Released under the MIT License.</p><p class="copyright" data-v-566314d4>Copyright © 2020-present</p></div></footer><!--[--><!--]--></div></div>
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