The work you want to perform, encapsulated in a way that lets you attach a completion handle or execution dependencies.
SDKs
Framework
class DispatchWorkItem
A Dispatch encapsulates work to be performed on a dispatch queue or within a dispatch group. You can also use a work item as a Dispatch event, registration, or cancellation handler.
init(qos: DispatchCreates a new dispatch work item from an existing block and assigns it the specified quality-of-service class.
struct DispatchA set of behaviors for a work item, such as its quality-of-service class and whether to create a barrier or spawn a new detached thread.
func perform()Executes the work item's block synchronously on the current thread.
func notify(queue: DispatchSchedules the execution of the specified work item after the completion of the current work item.
func notify(qos: DispatchSchedules the execution of the specified work item, with the specified quality-of-service, after the completion of the current work item.
func wait()Causes the caller to wait synchronously until the dispatch work item finishes executing.
func wait(timeout: DispatchCauses the caller to wait synchronously until the dispatch work item finishes executing, or until the specified time elapses.
func wait(wallCauses the caller to wait synchronously until the dispatch work item finishes executing, or until the specified time elapses.
struct DispatchA point in time relative to the default clock, with nanosecond precision.
struct DispatchAn absolute point in time according to the wall clock, with microsecond precision.
func cancel()Cancels the current work item asynchronously.
var isA Boolean value indicating whether the work item has been canceled.
class DispatchAn object that manages the execution of tasks serially or concurrently on your app's main thread or on a background thread.
class DispatchA group of tasks that you monitor as a single unit.