dropFirst(_:)

Declaration

func dropFirst(_ count: Int = 1) -> AsyncDropFirstSequence<Self>

Parameters

• count:

  The number of elements to drop from the beginning of the sequence. count must be greater than or equal to zero.

Return Value

An asynchronous sequence that drops the first count elements from the base sequence.

Discussion

Use dropFirst(_:) when you want to drop the first n elements from the base sequence and pass through the remaining elements.

In this example, an asynchronous sequence called Counter produces Int values from 1 to 10. The dropFirst(_:) method causes the modified sequence to ignore the values 1 through 3, and instead emit 4 through 10:

for await number in Counter(howHigh: 10).dropFirst(3) {
    print(number, terminator: " ")
}
// Prints "4 5 6 7 8 9 10 "

If the number of elements to drop exceeds the number of elements in the sequence, the result is an empty sequence.