Enhancements to the proposal Set methods

[unadlib]

This is a proposal https://github.com/tc39/proposal-set-methods to add methods like union and intersection to JavaScript's built-in Set class.

It is currently at stage 4: it has been tc39/ecma262#3306. This repository is no longer active.

This would add the following methods:

• Set.prototype.intersection(other)
• Set.prototype.union(other)
• Set.prototype.difference(other)
• Set.prototype.symmetricDifference(other)
• Set.prototype.isSubsetOf(other)
• Set.prototype.isSupersetOf(other)
• Set.prototype.isDisjointFrom(other)

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With the support of the latest major browsers, it is necessary for Mutative to support it as well.

Check compatibility

[unadlib]

Compatibility

	Version
Chrome	122
Edge	122
Firefox	127
Opera	108
Safari	17
Chrome Android	122
Firefox for Android	127
Opera Android	81
Safari on iOS	17
Samsung Internet	26.0
WebView Android	122
WebView on iOS	17
Deno	1.42
Node.js	22.0.0

[unadlib]

Here's a performance comparison of two different Set shallow copy methods. We have reason to use Set.prototype.difference to ensure optimal Set shallow copy performance.

This will allow Mutative's Set shallow copy performance to improve by 3X to 6X.

new Set(baseState.values());;

// vs 

baseState.difference(new Set());

[unadlib]

Based on the new Set shallow copy approach, Mutative's Set operation performance has improved from 3X to 4X faster compared to Immer.