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Struct template impl

boost::proto::lazy::impl

Synopsis

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


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

impl public types

  1. typedef see-below result_type;

    proto::lazy<T>::impl<Expr,State,Data>::result_type is calculated as follows:

    • If T if of the form O(A0,…An), then let O' be boost::result_of<proto::make<O>(Expr, State, Data)>::type and let T' be O'(A0,…An).

    • If T if of the form O(A0,…An ...), then let O' be boost::result_of<proto::make<O>(Expr, State, Data)>::type and let T' be O'(A0,…An ...).

    • Otherwise, let T' be boost::result_of<proto::make<T>(Expr, State, Data)>::type.

    The result type is boost::result_of<proto::call<T'>(Expr, State, Data)>::type .

impl public member functions

  1. result_type operator()(typename impl::expr_param expr, 
                           typename impl::state_param state, 
                           typename impl::data_param data) const;

    proto::lazy<T>::impl<Expr,State,Data>::operator() behaves as follows:

    • If T if of the form O(A0,…An), then let O' be boost::result_of<proto::make<O>(Expr, State, Data)>::type and let T' be O'(A0,…An).

    • If T if of the form O(A0,…An ...), then let O' be boost::result_of<proto::make<O>(Expr, State, Data)>::type and let T' be O'(A0,…An ...).

    • Otherwise, let T' be boost::result_of<proto::make<T>(Expr, State, Data)>::type.

    Returns:

    proto::call<T'>()(expr, state, data)


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