7 New JavaScript Set Methods

TL;DR: JavaScript’s Set data structure has added 7 new APIs that are very useful and can reduce the need for libraries like lodash. They are:

• intersection() returns a new set with elements in both this set and the given set.

• union() returns a new set with all elements in this set and the given set.

• difference() returns a new set with elements in this set but not in the given set.

• symmetricDifference() returns a new set with elements in either set, but not in both.

• isSubsetOf() returns a boolean indicating if all elements of a set are in a specific set.

• isSupersetOf() returns a boolean indicating if all elements of a set are in a specific set.

• isDisjointFrom() returns a boolean indicating if this set has no elements in common with a specific set.

1. Set.prototype.intersection()

The intersection() method of Set instances takes a set and returns a new set containing elements in both this set and the given set.

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Example:

2. Set.prototype.union()

The union() method of Set instances takes a set and returns a new set containing elements which are in either or both of this set and the given set.

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Example:

3. Set.prototype.difference()

The difference() method of Set instances takes a set and returns a new set containing elements in this set but not in the given set.

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Example:

4. Set.prototype.symmetricDifference()

The symmetricDifference() method of Set instances takes a set and returns a new set containing elements which are in either this set or the given set, but not in both.

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Example:

5. Set.prototype.isSubsetOf()

The isSubsetOf() method of Set instances takes a set and returns a boolean indicating if all elements of this set are in the given set.

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Example:

6. Set.prototype.isSupersetOf()

The isSupersetOf() method of Set instances takes a set and returns a boolean indicating if all elements of the given set are in this set.

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Example:

7. Set.prototype.isDisjointFrom()

The isDisjointFrom() method of Set instances takes a set and returns a boolean indicating if this set has no elements in common with the given set.

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Example:

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