# AsyncNodeBody

[req.async_node_body]

A type Body satisfies AsyncNodeBody if it meets the following requirements:

AsyncNodeBody Requirements: Pseudo-Signature, Semantics

Body::Body(const Body&)

  Copy constructor.

Body::~Body()

  Destructor.

void Body::operator()(const Input &v, GatewayType &gateway)

  Requirements:

  - The `Input` type must be the same as the `Input` template type argument of the `async_node` instance in which the `Body` object is passed during construction.

  - The `GatewayType` type must be the same as the `gateway_type` member type of the `async_node` instance in which the `Body` object is passed during construction.

  The input value `v` is submitted by the flow graph to an external activity. The gateway interface allows the external activity to communicate with the enclosing flow graph.