Instance Method

dropFirst(_:)

Returns a subsequence containing all but the given number of initial elements.

Declaration

func dropFirst(_ k: Int = 1) -> Substring

Parameters

k

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

Return Value

A subsequence starting after the specified number of elements.

Discussion

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

let numbers = [1, 2, 3, 4, 5]
print(numbers.dropFirst(2))
// Prints "[3, 4, 5]"
print(numbers.dropFirst(10))
// Prints "[]"

Complexity: O(1) if the collection conforms to RandomAccessCollection; otherwise, O(k), where k is the number of elements to drop from the beginning of the collection.

See Also

Removing Substrings

func remove(at: String.Index) -> Character

Removes and returns the character at the specified position.

func remove(at: Index) -> Character

Removes and returns the element at the specified position.

func removeAll(keepingCapacity: Bool)

Replaces this string with the empty string.

func removeAll(where: (Character) -> Bool)

Removes all the elements that satisfy the given predicate.

func removeFirst() -> Character

Removes and returns the first element of the collection.

func removeFirst(Int)

Removes the specified number of elements from the beginning of the collection.

func removeLast() -> Character

Removes and returns the last element of the collection.

func removeLast(Int)

Removes the specified number of elements from the end of the collection.

func removeSubrange(Range<String.Index>)

Removes the characters in the given range.

func removeSubrange(Range<Index>)

Removes the elements in the specified subrange from the collection.

func removeSubrange<R>(R)

Removes the elements in the specified subrange from the collection.

func filter((Character) -> Bool) -> String

Returns a new collection of the same type containing, in order, the elements of the original collection that satisfy the given predicate.

func drop(while: (Character) -> Bool) -> Substring

Returns a subsequence by skipping elements while predicate returns true and returning the remaining elements.

func dropLast(Int) -> Substring

Returns a subsequence containing all but the specified number of final elements.

func popLast() -> Character?

Removes and returns the last element of the collection.