choice Class

A choice messaging block is a multi-source, single-target block that represents a control-flow interaction with a set of sources. The choice block will wait for any one of multiple sources to produce a message and will propagate the index of the source that produced the message.

template<
   class _Type
>
class choice: public ISource<size_t>;

Parameters

_Type
A tuple-based type representing the payloads of the input sources.

Members

Public Typedefs

Name	Description
type	A type alias for _Type.

Public Constructors

Name	Description
choice::choice Constructor	Overloaded. Constructs a choice messaging block.
choice::~choice Destructor	Destroys the choice messaging block.

Public Methods

Name	Description
choice::accept Method	Accepts a message that was offered by this choice block, transferring ownership to the caller.
choice::acquire_ref Method	Acquires a reference count on this choice messaging block, to prevent deletion.
choice::consume Method	Consumes a message previously offered by this choice messaging block and successfully reserved by the target, transferring ownership to the caller.
choice::has_value Method	Checks whether this choice messaging block has been initialized with a value yet.
choice::index Method	Returns an index into the tuple representing the element selected by the choice messaging block.
choice::link_target Method	Links a target block to this choice messaging block.
choice::release Method	Releases a previous successful message reservation.
choice::release_ref Method	Releases a reference count on this choice messaging block.
choice::reserve Method	Reserves a message previously offered by this choice messaging block.
choice::unlink_target Method	Unlinks a target block from this choice messaging block.
choice::unlink_targets Method	Unlinks all targets from this choice messaging block. (Overrides ISource::unlink_targets.)
choice::value Method	Gets the message whose index was selected by the choice messaging block.

Remarks

The choice block ensures that only one of the incoming messages is consumed.

For more information, see Asynchronous Message Blocks.

Inheritance Hierarchy

ISource

choice

Requirements

Header: agents.h

Namespace: concurrency