copyWithin$ - nodef/extra-array GitHub Wiki

Copy part of array within!

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

function copyWithin$(x, j, i, I)
// x: an array (updated!)
// j: write index [0]
// i: read begin index [0]
// I: read end index [|x|]
const xarray = require('extra-array');

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

x;
// → [ 1, 2, 3, 1, 2 ]

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

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

References