Collection
protocol Collection : Sequence where Self.SubSequence : Collection
-
Mechanica
Returns the element at the specified index or nil if not exists.
Example:
let array = [1, 2, 3] array[100] -> crash array[safe: 100] -> nil
Declaration
Swift
public subscript(safe index: Index) -> Element? { get }
Parameters
index
the index of the desired element.
-
Mechanica
Example:
let array = [1, 2, 3] array[100] -> crash array.at(100) -> nil
Declaration
Swift
public func at(_ index: Index) -> Element?
Parameters
index
the index of the desired element.
Return Value
The element at a given index or nil if not exists.
-
Mechanica
Returns all the indices of a specified item.
Example:
[1, 2, 1, 2, 3, 4, 5, 1].indices(of: 1) -> [0, 2, 7])
Declaration
Swift
public func indices(of item: Element) -> [Index]
Parameters
item
item to verify.
Return Value
all the indices of the given item.