.. SPDX-FileCopyrightText: 2019-2021 Intel Corporation .. .. SPDX-License-Identifier: CC-BY-4.0

=========== buffer_node

[flow_graph.buffer_node]

A node that is an unbounded buffer of messages. Messages are forwarded in an arbitrary order.

.. code:: cpp

// Defined in header <oneapi/tbb/flow_graph.h>

namespace oneapi {
namespace tbb {
namespace flow {

    template< typename T>
    class buffer_node : public graph_node, public receiver<T>, public sender<T> {
    public:
        explicit buffer_node( graph &g );
        buffer_node( const buffer_node &src );
        ~buffer_node();

        bool try_put( const T &v );
        bool try_get( T &v );
    };

} // namespace flow
} // namespace tbb
} // namespace oneapi

Requirements:

The type T must meet the CopyConstructible requirements from [copyconstructible] and CopyAssignable requirements from [copyassignable] ISO C++ Standard sections.

buffer_node is a graph_node, receiver<T>, and sender<T>.

buffer_node has a buffering and single-push :doc:properties <forwarding_and_buffering>.

buffer_node forwards messages in an arbitrary order to a single successor in its successor set.

Member functions

.. cpp:function:: explicit buffer_node( graph &g )

Constructs an empty ``buffer_node`` that belongs to the graph ``g``.

.. cpp:function:: explicit buffer_node( const buffer_node &src )

Constructs an empty ``buffer_node`` that belongs to the same graph ``g`` as ``src``. Any
intermediate state of ``src``, including its links to predecessors and successors, is not
copied.

.. cpp:function:: bool try_put( const T &v )

Adds ``v`` to the set of items managed by the node, and tries forwarding it to a successor.

**Returns**: ``true``

.. cpp:function:: bool try_get( T &v )

**Returns**: ``true`` if an item can be removed from the node and assigned to ``v``.
Returns ``false`` if there is no non-reserved item currently in the node.