Discussion on: 1 line of code: How to remove all duplicates from an Array

View post

Worth explaining this separately when used with array instead of sets

const x = ["abc", "def"]
const y = [...x]
// ["abc", "def"]

And modifying x and y won't affect the other.

Then bringing in set

const x = ["abc", "def", "abc"]
const y = new Set(x)
// Set(["abc", "def"])
const z = [...y]
// ["abc", "def"]

And the the original post does that in one line in a function

Michael Currin • Oct 28 '21

Also worth adding that you might want to stop once you have a set and not convert it back to an array.

Why?

Lookup time from a set is constant to check if a value is in a set while in an array of 1000 elements worst case you have to go through 1000 elements until you find the one at the end.

Secondly when you convert from array to set, the order will be lost. Sets are inherently unordered. So when you convert from set to array you will not get the order of the original array. So you might as well keep the set.