Copies part of array within. :package: :smiley_cat: :running: :vhs: :moon: :scroll: :newspaper: :blue_book:

Alternatives: copyWithin, copyWithin$. Similar: copy, copyWithin, moveWithin.

This is part of package extra-array.

array.copyWithin(x, [j], [i], [I]);
// x: an array
// j: write index (0)
// i: read start index (0)
// I: read end index (X)

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

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

array.copyWithin(x, 3, 1);
// [ 1, 2, 3, 2, 3 ]

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

References

• Array.prototype.copyWithin: MDN web docs
• immutable-iterable-prototype: @azu