...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
boost::proto::call — Make the given CallableTransform into a PrimitiveTransform.
// In header: <boost/proto/transform/call.hpp> template<typename T> struct call : proto::transform< call> { // member classes/structs/unions template<typename Expr, typename State, typename Data> struct impl : proto::transform_impl { // 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; }; };
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.