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import{_ as i,o as a,c as n,ae as t}from"./chunks/framework.C8AWLET_.js";const o=JSON.parse('{"title":"🛑 Untracking: $.ignore( )","description":"","frontmatter":{},"headers":[],"relativePath":"api/ignore.md","filePath":"api/ignore.md"}'),e={name:"api/ignore.md"};function l(h,s,p,k,r,g){return a(),n("div",null,[...s[0]||(s[0]=[t(`<h1 id="🛑-untracking-ignore" tabindex="-1">🛑 Untracking: <code>$.ignore( )</code> <a class="header-anchor" href="#🛑-untracking-ignore" aria-label="Permalink to &quot;🛑 Untracking: \`$.ignore( )\`&quot;"></a></h1><p>The <code>$.ignore</code> function allows you to read a signal&#39;s value inside an effect or a computed signal <strong>without</strong> creating a dependency.</p><h2 id="🛠-function-signature" tabindex="-1">🛠 Function Signature <a class="header-anchor" href="#🛠-function-signature" aria-label="Permalink to &quot;🛠 Function Signature&quot;"></a></h2><div class="language-typescript vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">typescript</span><pre class="shiki shiki-themes github-light github-dark vp-code" tabindex="0"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">$.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">ignore</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(callback: Function): any</span></span></code></pre></div><table tabindex="0"><thead><tr><th style="text-align:left;">Parameter</th><th style="text-align:left;">Type</th><th style="text-align:left;">Required</th><th style="text-align:left;">Description</th></tr></thead><tbody><tr><td style="text-align:left;"><strong><code>callback</code></strong></td><td style="text-align:left;"><code>Function</code></td><td style="text-align:left;">Yes</td><td style="text-align:left;">A function where signals can be read &quot;silently&quot;.</td></tr></tbody></table><p><strong>Returns:</strong> Whatever the callback function returns.</p><hr><h2 id="📖-usage-patterns" tabindex="-1">📖 Usage Patterns <a class="header-anchor" href="#📖-usage-patterns" aria-label="Permalink to &quot;📖 Usage Patterns&quot;"></a></h2><h3 id="_1-preventing-dependency-tracking" tabindex="-1">1. Preventing Dependency Tracking <a class="header-anchor" href="#_1-preventing-dependency-tracking" aria-label="Permalink to &quot;1. Preventing Dependency Tracking&quot;"></a></h3><p>Normally, reading a signal inside <code>$.effect</code> makes the effect re-run when that signal changes. <code>$.ignore</code> breaks this link.</p><div class="language-javascript vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">javascript</span><pre class="shiki shiki-themes github-light github-dark vp-code" tabindex="0"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> count</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> $</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">0</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">);</span></span>
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> logLabel</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> $</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;System Log&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">);</span></span>
<span class="line"></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">$.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">effect</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(() </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;"> // This effect tracks &#39;count&#39;...</span></span>
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> currentCount</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> count</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">();</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> </span></span>
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"> // ...but NOT &#39;logLabel&#39;. </span></span>
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"> // Changing &#39;logLabel&#39; will NOT re-run this effect.</span></span>
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> label</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> $.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">ignore</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;"> logLabel</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">());</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> </span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> console.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">log</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">\`\${</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">label</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">}: \${</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">currentCount</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">}\`</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">);</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">});</span></span>
<span class="line"></span>
<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">count</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">1</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">); </span><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Console: &quot;System Log: 1&quot; (Triggers re-run)</span></span>
<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">logLabel</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#032F62;--shiki-dark:#9ECBFF;">&quot;UI&quot;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">); </span><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;">// Nothing happens in console (Ignored)</span></span></code></pre></div><h3 id="_2-reading-state-in-event-handlers" tabindex="-1">2. Reading State in Event Handlers <a class="header-anchor" href="#_2-reading-state-in-event-handlers" aria-label="Permalink to &quot;2. Reading State in Event Handlers&quot;"></a></h3><p>Inside complex UI logic, you might want to take a &quot;snapshot&quot; of a signal without triggering a reactive chain.</p><div class="language-javascript vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">javascript</span><pre class="shiki shiki-themes github-light github-dark vp-code" tabindex="0"><code><span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">const</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> handleClick</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;">=&gt;</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> {</span></span>
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"> // Accessing state without letting the caller know we touched it</span></span>
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> data</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> $.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">ignore</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(() </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">=&gt;</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> mySignal</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">());</span></span>
<span class="line"><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> process</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(data);</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">};</span></span></code></pre></div><h3 id="_3-avoiding-infinite-loops" tabindex="-1">3. Avoiding Infinite Loops <a class="header-anchor" href="#_3-avoiding-infinite-loops" aria-label="Permalink to &quot;3. Avoiding Infinite Loops&quot;"></a></h3><p>If you need to <strong>write</strong> to a signal based on its own value inside an effect (and you aren&#39;t using the functional updater), <code>$.ignore</code> prevents the effect from triggering itself.</p><div class="language-javascript vp-adaptive-theme"><button title="Copy Code" class="copy"></button><span class="lang">javascript</span><pre class="shiki shiki-themes github-light github-dark vp-code" tabindex="0"><code><span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">$.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">effect</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(() </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:#D73A49;--shiki-dark:#F97583;"> const</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> value</span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> =</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;"> someSignal</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">();</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> </span></span>
<span class="line"><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;"> if</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> (value </span><span style="--shiki-light:#D73A49;--shiki-dark:#F97583;">&gt;</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;"> 100</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">) {</span></span>
<span class="line"><span style="--shiki-light:#6A737D;--shiki-dark:#6A737D;"> // We update the signal, but we ignore the read to avoid a loop</span></span>
<span class="line"><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;"> $.</span><span style="--shiki-light:#6F42C1;--shiki-dark:#B392F0;">ignore</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;"> someSignal</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">(</span><span style="--shiki-light:#005CC5;--shiki-dark:#79B8FF;">0</span><span style="--shiki-light:#24292E;--shiki-dark:#E1E4E8;">));</span></span>
<span class="line"><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><hr><h2 id="💡-why-use-it" tabindex="-1">💡 Why use it? <a class="header-anchor" href="#💡-why-use-it" aria-label="Permalink to &quot;💡 Why use it?&quot;"></a></h2><ul><li><strong>Performance:</strong> Prevents expensive effects from running when non-essential data changes.</li><li><strong>Logic Control:</strong> Allows &quot;sampling&quot; a signal at a specific point in time.</li><li><strong>Safety:</strong> Essential for complex state orchestrations where circular dependencies might occur.</li></ul>`,20)])])}const c=i(e,[["render",l]]);export{o as __pageData,c as default};