Instance Method

formIndex(_:offsetBy:)

Offsets the given index by the specified distance.

Declaration

func formIndex(_ i: inout Int, offsetBy distance: Int)

Parameters

i

A valid index of the collection.

distance

The distance to offset i. distance must not be negative unless the collection conforms to the BidirectionalCollection protocol.

Discussion

The value passed as distance must not offset i beyond the bounds of the collection.

Complexity: O(1) if the collection conforms to RandomAccessCollection; otherwise, O(k), where k is the absolute value of distance.