Instance Method

contains(_:)

Returns a Boolean value indicating whether the sequence contains the given element.

Declaration

func contains(_ element: Element) -> Bool
Available when Element conforms to Equatable.

Parameters

element

The element to find in the sequence.

Return Value

true if the element was found in the sequence; otherwise, false.

Discussion

This example checks to see whether a favorite actor is in an array storing a movie’s cast.

let cast = ["Vivien", "Marlon", "Kim", "Karl"]
print(cast.contains("Marlon"))
// Prints "true"
print(cast.contains("James"))
// Prints "false"

Complexity: O(n), where n is the length of the sequence.

See Also

Finding Elements

func contains(where: (Element) -> Bool) -> Bool

Returns a Boolean value indicating whether the sequence contains an element that satisfies the given predicate.

func allSatisfy((Element) -> Bool) -> Bool

Returns a Boolean value indicating whether every element of a sequence satisfies a given predicate.

func first(where: (Element) -> Bool) -> Element?

Returns the first element of the sequence that satisfies the given predicate.

func firstIndex(of: Element) -> Int?

Returns the first index where the specified value appears in the collection.

func index(of: Element) -> Int?

Returns the first index where the specified value appears in the collection.

Deprecated
func firstIndex(where: (Element) -> Bool) -> Int?

Returns the first index in which an element of the collection satisfies the given predicate.

func last(where: (Element) -> Bool) -> Element?

Returns the last element of the sequence that satisfies the given predicate.

func lastIndex(of: Element) -> Int?

Returns the last index where the specified value appears in the collection.

func lastIndex(where: (Element) -> Bool) -> Int?

Returns the index of the last element in the collection that matches the given predicate.

func min() -> Element?

Returns the minimum element in the sequence.

func min(by: (Element, Element) -> Bool) -> Element?

Returns the minimum element in the sequence, using the given predicate as the comparison between elements.

func max() -> Element?

Returns the maximum element in the sequence.

func max(by: (Element, Element) -> Bool) -> Element?

Returns the maximum element in the sequence, using the given predicate as the comparison between elements.