Flattens nested array to given depth. :package: :smiley_cat: :running: :vhs: :moon: :scroll: :newspaper: :blue_book:

Alternatives: flat, flatMap.

This is part of package extra-array.

array.flat(x, [n], [fm], [ft]);
// x:  a nested array
// n:  maximum depth (-1 => all)
// fm: map function (v, i, x)
// ft: test function (v, i, x)

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

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

array.flat(x, 1);
// [ 1, 2, 3, [ 4, [ 5 ] ] ]

array.flat(x, 2);
// [ 1, 2, 3, 4, [ 5 ] ]

References

• Array.prototype.flat: MDN web docs
• _.flatten: lodash
• _.flattenDeep: lodash
• _.flattenDepth: lodash
• Array.flatten: sugarjs