Gives values present in any array. :package: :smiley_cat: :running: :vhs: :moon: :scroll: :newspaper: :blue_book:

Alternatives: union, union$. Similar: union, intersection, difference, symmetricDifference.

This is part of package extra-array.

array.union(x, y, [fc], [fm]);
// x:  an array
// y:  another array
// fc: compare function (a, b)
// fm: map function (v, i, x)

:stopwatch: Compare function => O(n²).

const array = require("extra-array");

var x = [1, 2, 3, 4];
var y = [2, 3, 5];
array.union(x, y);
// [ 1, 2, 3, 4, 5 ]

var y = [-2, -3, -5];
array.union(x, y, (a, b) => Math.abs(a) - Math.abs(b));
// [ 1, 2, 3, 4, -5 ]

array.union(x, y, null, v => Math.abs(v));
// [ 1, 2, 3, 4, -5 ]

References

• Data.Set.union: Haskell
• Set.union: Python
• _.union: lodash
• _.unionBy: lodash
• _.unionWith: lodash
• Array.union: sugarjs