Instance Method


Offsets the given index by the specified distance.


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



A valid index of the collection.


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


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.

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