Generic Instance Method

replaceSubrange(_:with:)

Replaces the specified subrange of elements with the given collection.

Declaration

mutating func replaceSubrange<C, R>(_ subrange: R, with newElements: C) where C : Collection, R : RangeExpression, Self.Element == C.Element, Self.Index == R.Bound

Parameters

subrange

The subrange of the collection to replace. The bounds of the range must be valid indices of the collection.

newElements

The new elements to add to the collection.

Discussion

This method has the effect of removing the specified range of elements from the collection and inserting the new elements at the same location. The number of new elements need not match the number of elements being removed.

In this example, three elements in the middle of an array of integers are replaced by the five elements of a Repeated<Int> instance.

 var nums = [10, 20, 30, 40, 50]
 nums.replaceSubrange(1...3, with: repeatElement(1, count: 5))
 print(nums)
 // Prints "[10, 1, 1, 1, 1, 1, 50]"

If you pass a zero-length range as the subrange parameter, this method inserts the elements of newElements at subrange.startIndex. Calling the insert(contentsOf:at:) method instead is preferred.

Likewise, if you pass a zero-length collection as the newElements parameter, this method removes the elements in the given subrange without replacement. Calling the removeSubrange(_:) method instead is preferred.

Calling this method may invalidate any existing indices for use with this collection.

Complexity: O(n + m), where n is length of this collection and m is the length of newElements. If the call to this method simply appends the contents of newElements to the collection, the complexity is O(m).

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