Replicating Array Elements in JavaScript
In Python, multiplying a list by a number replicates its elements that many times. For instance, [2] * 5 yields [2, 2, 2, 2, 2]. Can we replicate this functionality in JavaScript using arrays?
Custom Function
One approach is to define a function like the following:
<code class="javascript">var repeatelem = function(elem, n){ // returns an array with element elem repeated n times. var arr = []; for (var i = 0; i <h3 id="ES-fill-Method">ES6 fill() Method</h3> <p>However, starting with ES6, JavaScript introduced the Array.fill() method, which provides a more concise and efficient solution:</p> <pre class="brush:php;toolbar:false"><code class="javascript">console.log( Array(5).fill(2) ) //=> [2, 2, 2, 2, 2]</code>
Here, Array(5) creates an empty array of length 5, and .fill(2) populates it with the provided element (2). This approach is both shorter and faster than the custom function, offering a clean and convenient way to replicate array elements in JavaScript.
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