multifunction_node¶
[flow_graph.multifunction_node]
A node that used for nodes that receive messages at a single input port and may generate one or more messages that are broadcast to successors.
// Defined in header <oneapi/tbb/flow_graph.h>
namespace oneapi {
namespace tbb {
namespace flow {
template < typename Input, typename Output, typename Policy = /*implementation-defined*/ >
class multifunction_node : public graph_node, public receiver<Input> {
public:
template<typename Body>
multifunction_node( graph &g, size_t concurrency, Body body, Policy /*unspecified*/ = Policy(),
node_priority_t priority = no_priority );
template<typename Body>
multifunction_node( graph &g, size_t concurrency, Body body,
node_priority_t priority = no_priority );
multifunction_node( const multifunction_node& other );
~multifunction_node();
bool try_put( const Input &v );
using output_ports_type = /*implementation-defined*/;
output_ports_type& output_ports();
};
} // namespace flow
} // namespace tbb
} // namespace oneapi
Requirements:
The
Inputtype must meet the DefaultConstructible requirements from [defaultconstructible] and the CopyConstructible requirements from [copyconstructible] ISO C++ Standard sections.The type
Policycan be specified as lightweight, queueing and rejecting policies or defaulted.The type
Bodymust meet the MultifunctionNodeBody requirements.
multifunction_node has a user-settable concurrency limit. It can be set to one of predefined values.
The user can also provide a value of type std::size_t to limit concurrency to a value between 1 and tbb::flow::unlimited.
When the concurrency limit allows, it executes the user-provided body on incoming messages. The body can create one or more output messages and broadcast them to successors.
multifunction_node is a graph_node, receiver<InputType> and has a tuple of
sender<Output> outputs.
multifunction_node has a discarding and broadcast-push properties.
The body object passed to a multifunction_node is copied. Updates to member variables do
not affect the original object used to construct the node. If the state held within a body object
must be inspected from outside of the node, the copy_body function can be
used to obtain an updated copy.
Member types¶
output_ports_type is an alias to a std::tuple of output ports.
Member functions¶
template<typename Body>
multifunction_node( graph &g, size_t concurrency, Body body,
node_priority_t priority = no_priority );
Constructs a multifunction_node that invokes a copy of body. Most concurrency calls
to body can be made concurrently.
Use this function to specify node priority.
template<typename Body>
multifunction_node( graph &g, size_t concurrency, Body body, Policy /*unspecified*/ = Policy(),
node_priority_t priority = no_priority );
Constructs a multifunction_node that invokes a copy of body. Most concurrency calls
to body can be made concurrently.
Use this function to specify a policy and node priority.
multifunction_node( const multifunction_node &src )
Constructs a multifunction_node that has the same initial
state that other had when it was constructed. The
multifunction_node that is constructed has a reference
to the same graph object as other, has a copy of the
initial body used by other, and has the same concurrency
threshold as other. The predecessors and successors of
other are not copied.
The new body object is copy-constructed from a copy of the
original body provided to other at its construction. Changes made to member variables in other body after the
construction of other do not affect the body of the new
multifunction_node.
bool try_put( const input_type &v )
If the concurrency limit allows, executes the user-provided body on the incoming message v.
Otherwise, depending on the policy of the node, either queues the incoming message v or rejects
it.
Returns: true if the input was accepted; false, otherwise.
output_ports_type& output_ports();
Returns: a std::tuple of output ports.