Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

Struct template call

Struct template call

boost::proto::call — Make the given CallableTransform into a PrimitiveTransform.

Synopsis

// In header: <boost/proto/transform/call.hpp>

template<typename T> 
struct call :  proto::transform< call<T> > {
  // member classes/structs/unions
  template<typename Expr, typename State, typename Data> 
  struct impl :  proto::transform_impl<Expr, State, Data> {
    // types
    typedef see-below result_type;

    // public member functions
    result_type operator()(typename impl::expr_param, 
                           typename impl::state_param, 
                           typename impl::data_param) const;
  };
};

Description

The purpose of proto::call<> is to annotate a transform as callable so that proto::when<> knows how to apply it. The template parameter must be either a PrimitiveTransform or a CallableTransform; that is, a function type for which the return type is a callable PolymorphicFunctionObject.

For the complete description of the behavior of the proto::call<> transform, see the documentation for the nested proto::call::impl<> class template.