how to check if a set is a subset of another set in javascript

To check if a set is a subset of another set in javascript, we can use the subset() method of the Set object. This method returns a boolean value indicating whether the set is a subset of another set.

Here is an example:

index.tsx
const set1 = new Set([1, 2, 3]);
const set2 = new Set([2, 3]);

const isSubset = [...set2].every((value) => set1.has(value));

console.log(isSubset); // true
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In the example above, we have two sets: set1 and set2. We want to check whether set2 is a subset of set1. We do this by converting set2 to an array using the spread operator (...), and then calling the every() method on the array. The every() method applies a test function to each element of the array and returns true if all elements pass the test. In this case, the test function checks whether each element of set2 exists in set1. If all elements of set2 exist in set1, then every() returns true and we know that set2 is a subset of set1.

Note that this method works for sets of any type of values, not just integers.