<pre class="shiki github-dark shaku"><code>/** * @param {Array&lt;any&gt;} promises - notice input might have non-Promises * @return {Promise&lt;any[]&gt;} */function all(promises) { return new Promise((resolve, reject) =&gt; { if (promises.length === 0) { resolve([]); return; } let completedCount = 0; const arrayRes = []; promises.forEach((val, index) =&gt; { Promise.resolve(val) .then((res) =&gt; { completedCount++; arrayRes[index] = res; if (promises.length === completedCount) { resolve(arrayRes); } }) .catch((res) =&gt; reject(res)); }); });}</code></pre>

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> The Promise.all() method takes an iterable of promises as an input, and returns a single Promise that resolves to an array of the results of the inp…