.. SPDX-FileCopyrightText: 2019-2020 Intel Corporation .. .. SPDX-License-Identifier: CC-BY-4.0 ====================== JoinNodeFunctionObject ====================== **[req.join_node_function_object]** A type `Func` satisfies `JoinNodeFunctionObject` if it meets the following requirements: ---------------------------------------------------------------------- **JoinNodeFunctionObject Requirements: Pseudo-Signature, Semantics** .. cpp:function:: Func::Func( const Func& ) Copy constructor. .. cpp:function:: Func::~Func() Destructor. .. cpp:function:: Key Func::operator()( const Input& v ) **Requirements:** The ``Key`` and ``Input`` types must be the same as the ``K`` and the corresponding element of the ``OutputTuple`` template arguments of the ``join_node`` instance to which the ``Func`` object is passed during construction. Returns key to be used for hashing input messages.