uikit

Operation & OperationQueue

Operations are an object-oriented way to encapsulate work that you want to perform asynchronously. Operations are designed to be used either in conjunction with an operation queue or by themselves Operations State An o...

DispatchSemaphore

An object that controls access to a resource across multiple execution contexts through use of a traditional counting semaphore. A dispatch semaphore is an efficient implementation of a traditional counting semaphore....