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copyWithin(target, start = 0, end = Enumerable length)

Create a new Enumerable copying part of an Enumerable to another location in the same Enumerable, without modifying its size. This is the equivalent of Array.prototype.copyWithin

Arguments

  • target (Number): index at which to copy the sequence to. If negative, target will be counted from the end.
  • start (Number): index at which to start copying elements from. If negative, start will be counted from the end.
  • end (Number): index at which to end copying elements from. copyWithin copies up to but not including end. If negative, end will be counted from the end.

Returns

(Enumerable): New modified Enumerable.

Example

Enumerable
        .from([1, 2, 3, 4, 5])
        .copyWithin(-2)
        .toArray();
// [1, 2, 3, 1, 2]

Enumerable
        .from([1, 2, 3, 4, 5])
        .copyWithin(0, 3)
        .toArray();
// [4, 5, 3, 4, 5]

Enumerable
        .from([1, 2, 3, 4, 5])
        .copyWithin(0, 3, 4)
        .toArray();
// [4, 2, 3, 4, 5]