The number of elements in the collection.
Required. Default implementation provided.
SDK
- Xcode 10.0+
Framework
- Swift Standard Library
Declaration
var count: Int { get }
Discussion
To check whether a collection is empty, use its is property instead of comparing count to zero. Unless the collection guarantees random-access performance, calculating count can be an O(n) operation.
Complexity: O(1) if the collection conforms to Random; otherwise, O(n), where n is the length of the collection.