New JavaScript Set methods are landing across browsers. Learn about sets, how you can use these methods to compare different sets, create new sets with specific properties, and more.

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New JavaScript Set methods such as intersection, union, difference, symmetricDifference, isSubsetOf, isSupersetOf, and isDisjointFrom have become available across most major browser engines without the need for polyfills. These methods facilitate various set operations, making it easier to perform operations like finding common elements, combining sets, and checking subset or superset relationships. Sets in JavaScript offer advantages for unique collections and performance improvements over arrays when dealing with larger datasets.

New JavaScript Set methods

<p>This is very useful, I always wonder why I should use Set over Array, and these methods answer.</p>


<p>woo hoo, thanks for sharing 🙌 really helpful
here is a TLDR:</p>
<h1>New Set Methods</h1>
<blockquote>
<p>JavaScript’s Set object now includes new methods available in major browsers like Firefox 127, eliminating the need for polyfills1.</p>
</blockquote>
<h2>Set Advantages</h2>
<blockquote>
<p>Sets ensure unique values and offer performance benefits over arrays, especially with large data sets.</p>
</blockquote>
<h2>Method Examples</h2>
<blockquote>
<p>The article provides examples of union, intersection, symmetric difference, and set difference methods for combining or comparing sets.</p>
</blockquote>
<h2>Boolean Operations</h2>
<blockquote>
<p>New methods like <code>isSubsetOf</code>, <code>isSupersetOf</code>, and <code>isDisjointFrom</code> perform logical checks and return Boolean values.</p>
</blockquote>


<p>I know a lot of people hate on JS but idk why it gets better every year</p>


<p>Thanks for sharing. You now see clearly when to use Set over an array.</p>
