to each.</p>
<p>Returns <code>true</code> if the event had listeners, <code>false</code> otherwise.</p>
<pre><code class="language-js"><span class="hl-5">import</span><span class="hl-0"> { </span><span class="hl-3">EventEmitter</span><span class="hl-0"> } </span><span class="hl-5">from</span><span class="hl-0"> </span><span class="hl-6">'node:events'</span><span class="hl-0">;</span><br/><span class="hl-4">const</span><span class="hl-0"> </span><span class="hl-7">myEmitter</span><span class="hl-0"> = </span><span class="hl-4">new</span><span class="hl-0"> </span><span class="hl-2">EventEmitter</span><span class="hl-0">();</span><br/><br/><span class="hl-8">// First listener</span><br/><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">on</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">, </span><span class="hl-4">function</span><span class="hl-0"> </span><span class="hl-2">firstListener</span><span class="hl-0">() {</span><br/><span class="hl-0"> </span><span class="hl-3">console</span><span class="hl-0">.</span><span class="hl-2">log</span><span class="hl-0">(</span><span class="hl-6">'Helloooo! first listener'</span><span class="hl-0">);</span><br/><span class="hl-0">});</span><br/><span class="hl-8">// Second listener</span><br/><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">on</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">, </span><span class="hl-4">function</span><span class="hl-0"> </span><span class="hl-2">secondListener</span><span class="hl-0">(</span><span class="hl-3">arg1</span><span class="hl-0">, </span><span class="hl-3">arg2</span><span class="hl-0">) {</span><br/><span class="hl-0"> </span><span class="hl-3">console</span><span class="hl-0">.</span><span class="hl-2">log</span><span class="hl-0">(</span><span class="hl-6">`event with parameters </span><span class="hl-4">${</span><span class="hl-3">arg1</span><span class="hl-4">}</span><span class="hl-6">, </span><span class="hl-4">${</span><span class="hl-3">arg2</span><span class="hl-4">}</span><span class="hl-6"> in second listener`</span><span class="hl-0">);</span><br/><span class="hl-0">});</span><br/><span class="hl-8">// Third listener</span><br/><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">on</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">, </span><span class="hl-4">function</span><span class="hl-0"> </span><span class="hl-2">thirdListener</span><span class="hl-0">(...</span><span class="hl-3">args</span><span class="hl-0">) {</span><br/><span class="hl-0"> </span><span class="hl-4">const</span><span class="hl-0"> </span><span class="hl-7">parameters</span><span class="hl-0"> = </span><span class="hl-3">args</span><span class="hl-0">.</span><span class="hl-2">join</span><span class="hl-0">(</span><span class="hl-6">', '</span><span class="hl-0">);</span><br/><span class="hl-0"> </span><span class="hl-3">console</span><span class="hl-0">.</span><span class="hl-2">log</span><span class="hl-0">(</span><span class="hl-6">`event with parameters </span><span class="hl-4">${</span><span class="hl-3">parameters</span><span class="hl-4">}</span><span class="hl-6"> in third listener`</span><span class="hl-0">);</span><br/><span class="hl-0">});</span><br/><br/><span class="hl-3">console</span><span class="hl-0">.</span><span class="hl-2">log</span><span class="hl-0">(</span><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">listeners</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">));</span><br/><br/><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">emit</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">, </span><span class="hl-1">1</span><span class="hl-0">, </span><span class="hl-1">2</span><span class="hl-0">, </span><span class="hl-1">3</span><span class="hl-0">, </span><span class="hl-1">4</span><span class="hl-0">, </span><span class="hl-1">5</span><span class="hl-0">);</span><br/><br/><span class="hl-8">// Prints:</span><br/><span class="hl-8">// [</span><br/><span class="hl-8">// [Function: firstListener],</span><br/><span class="hl-8">// [Function: secondListener],</span><br/><span class="hl-8">// [Function: thirdListener]</span><br/><span class="hl-8">// ]</span><br/><span class="hl-8">// Helloooo! first listener</span><br/><span class="hl-8">// event with parameters 1, 2 in second listener</span><br/><span class="hl-8">// event with parameters 1, 2, 3, 4, 5 in third listener</span>
</code><button>Copy</button></pre>
</div><div class="tsd-parameters"><h4 class="tsd-parameters-title">Parameters</h4><ul class="tsd-parameter-list"><li><h5><span class="tsd-kind-parameter">eventName</span>: <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol"> | </span><span class="tsd-signature-type">symbol</span></h5></li><li><h5><code class="tsd-tag ts-flagRest">Rest</code> <span class="tsd-signature-symbol">...</span><span class="tsd-kind-parameter">args</span>: <span class="tsd-signature-type">any</span><span class="tsd-signature-symbol">[]</span></h5></li></ul></div><h4 class="tsd-returns-title">Returns <span class="tsd-signature-type">boolean</span></h4><div class="tsd-comment tsd-typography"><h4>Since</h4><p>v0.1.26</p>
to each.</p>
<p>Returns <code>true</code> if the event had listeners, <code>false</code> otherwise.</p>
<pre><code class="language-js"><span class="hl-5">import</span><span class="hl-0"> { </span><span class="hl-3">EventEmitter</span><span class="hl-0"> } </span><span class="hl-5">from</span><span class="hl-0"> </span><span class="hl-6">'node:events'</span><span class="hl-0">;</span><br/><span class="hl-4">const</span><span class="hl-0"> </span><span class="hl-7">myEmitter</span><span class="hl-0"> = </span><span class="hl-4">new</span><span class="hl-0"> </span><span class="hl-2">EventEmitter</span><span class="hl-0">();</span><br/><br/><span class="hl-8">// First listener</span><br/><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">on</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">, </span><span class="hl-4">function</span><span class="hl-0"> </span><span class="hl-2">firstListener</span><span class="hl-0">() {</span><br/><span class="hl-0"> </span><span class="hl-3">console</span><span class="hl-0">.</span><span class="hl-2">log</span><span class="hl-0">(</span><span class="hl-6">'Helloooo! first listener'</span><span class="hl-0">);</span><br/><span class="hl-0">});</span><br/><span class="hl-8">// Second listener</span><br/><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">on</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">, </span><span class="hl-4">function</span><span class="hl-0"> </span><span class="hl-2">secondListener</span><span class="hl-0">(</span><span class="hl-3">arg1</span><span class="hl-0">, </span><span class="hl-3">arg2</span><span class="hl-0">) {</span><br/><span class="hl-0"> </span><span class="hl-3">console</span><span class="hl-0">.</span><span class="hl-2">log</span><span class="hl-0">(</span><span class="hl-6">`event with parameters </span><span class="hl-4">${</span><span class="hl-3">arg1</span><span class="hl-4">}</span><span class="hl-6">, </span><span class="hl-4">${</span><span class="hl-3">arg2</span><span class="hl-4">}</span><span class="hl-6"> in second listener`</span><span class="hl-0">);</span><br/><span class="hl-0">});</span><br/><span class="hl-8">// Third listener</span><br/><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">on</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">, </span><span class="hl-4">function</span><span class="hl-0"> </span><span class="hl-2">thirdListener</span><span class="hl-0">(...</span><span class="hl-3">args</span><span class="hl-0">) {</span><br/><span class="hl-0"> </span><span class="hl-4">const</span><span class="hl-0"> </span><span class="hl-7">parameters</span><span class="hl-0"> = </span><span class="hl-3">args</span><span class="hl-0">.</span><span class="hl-2">join</span><span class="hl-0">(</span><span class="hl-6">', '</span><span class="hl-0">);</span><br/><span class="hl-0"> </span><span class="hl-3">console</span><span class="hl-0">.</span><span class="hl-2">log</span><span class="hl-0">(</span><span class="hl-6">`event with parameters </span><span class="hl-4">${</span><span class="hl-3">parameters</span><span class="hl-4">}</span><span class="hl-6"> in third listener`</span><span class="hl-0">);</span><br/><span class="hl-0">});</span><br/><br/><span class="hl-3">console</span><span class="hl-0">.</span><span class="hl-2">log</span><span class="hl-0">(</span><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">listeners</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">));</span><br/><br/><span class="hl-3">myEmitter</span><span class="hl-0">.</span><span class="hl-2">emit</span><span class="hl-0">(</span><span class="hl-6">'event'</span><span class="hl-0">, </span><span class="hl-1">1</span><span class="hl-0">, </span><span class="hl-1">2</span><span class="hl-0">, </span><span class="hl-1">3</span><span class="hl-0">, </span><span class="hl-1">4</span><span class="hl-0">, </span><span class="hl-1">5</span><span class="hl-0">);</span><br/><br/><span class="hl-8">// Prints:</span><br/><span class="hl-8">// [</span><br/><span class="hl-8">// [Function: firstListener],</span><br/><span class="hl-8">// [Function: secondListener],</span><br/><span class="hl-8">// [Function: thirdListener]</span><br/><span class="hl-8">// ]</span><br/><span class="hl-8">// Helloooo! first listener</span><br/><span class="hl-8">// event with parameters 1, 2 in second listener</span><br/><span class="hl-8">// event with parameters 1, 2, 3, 4, 5 in third listener</span>
</code><button>Copy</button></pre>
</div><div class="tsd-parameters"><h4 class="tsd-parameters-title">Parameters</h4><ul class="tsd-parameter-list"><li><h5><span class="tsd-kind-parameter">eventName</span>: <span class="tsd-signature-type">string</span><span class="tsd-signature-symbol"> | </span><span class="tsd-signature-type">symbol</span></h5></li><li><h5><code class="tsd-tag ts-flagRest">Rest</code> <span class="tsd-signature-symbol">...</span><span class="tsd-kind-parameter">args</span>: <span class="tsd-signature-type">any</span><span class="tsd-signature-symbol">[]</span></h5></li></ul></div><h4 class="tsd-returns-title">Returns <span class="tsd-signature-type">boolean</span></h4><div class="tsd-comment tsd-typography"><h4>Since</h4><p>v0.1.26</p>