The task_group class represents a collection of parallel work which can be waited on or canceled.
Constructs a new task_group object.
Destroys a task_group object. You are expected to call the either the wait or run_and_wait method on the object prior to the destructor executing, unless the destructor is executing as the result of stack unwinding due to an exception.
Makes a best effort attempt to cancel the sub-tree of work rooted at this task group. Every task scheduled on the task group will get canceled transitively if possible.
Informs the caller whether or not the task group is currently in the midst of a cancellation. This does not necessarily indicate that the cancel method was called on the task_group object (although such certainly qualifies this method to return true). It may be the case that the task_group object is executing inline and a task group further up in the work tree was canceled. In cases such as these where the runtime can determine ahead of time that cancellation will flow through this task_group object, true will be returned as well.
Overloaded. Schedules a task on the task_group object. If a task_handle object is passed as a parameter to run, the caller is responsible for managing the lifetime of the task_handle object. The version of the method that takes a reference to a function object as a parameter involves heap allocation inside the runtime which may be perform less well than using the version that takes a reference to a task_handle object.
Overloaded. Schedules a task to be run inline on the calling context with the assistance of the task_group object for full cancellation support. The function then waits until all work on the task_group object has either completed or been canceled. If a task_handle object is passed as a parameter to run_and_wait, the caller is responsible for managing the lifetime of the task_handle object.
Waits until all work on the task_group object has either completed or been canceled.
Unlike the heavily restricted structured_task_group class, the task_group class is much more general construct. It does not have any of the restrictions described by structured_task_group. task_group objects may safely be used across threads and utilized in free-form ways. The disadvantage of the task_group construct is that it may not perform as well as the structured_task_group construct for tasks which perform small amounts of work.
For more information, see Task Parallelism (Concurrency Runtime).