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

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

This is part of package extra-array.

This is browserified, minified version of @extra-array/copy-update. It is exported as global variable array_copy$. CDN: unpkg, jsDelivr.

array.copy$(x, y, [j], [i], [I]);
// x: target array (updated)
// y: source array
// j: write index (0)
// i: read start index (0)
// I: read end index (X)
// → x

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

var x = [1, 2, 3, 4, 5];
var y = [10, 20, 30];
array.copy$(x, y);
// [ 10, 20, 30, 4, 5 ]

x;
// [ 10, 20, 30, 4, 5 ]

var x = [1, 2, 3, 4, 5];
array.copy$(x, y, 1);
// [ 1, 10, 20, 30, 5 ]

var x = [1, 2, 3, 4, 5];
array.copy$(x, y, 1, 1);
// [ 1, 20, 30, 4, 5 ]

var x = [1, 2, 3, 4, 5];
array.copy$(x, y, 1, 1, 2);
// [1, 20, 3, 4, 5]

References

• Array.prototype.copyWithin: MDN web docs
• Collections.copy: Java