Struct template impl

Boost C++ Libraries

Struct template impl

boost::proto::if_::impl

Synopsis

// In header: <boost/proto/matches.hpp>


template<typename Expr, typename State, typename Data> 
struct impl :  proto::transform_impl< Expr, State, Data > {
  // types
  typedef typename mpl::if_<
      typename boost::result_of<proto::when<proto::_, If>(Expr, State, Data)>::type,
      typename boost::result_of<proto::when<proto::_, Then>(Expr, State, Data)>::type,
      typename boost::result_of<proto::when<proto::_, Else>(Expr, State, Data)>::type
    >::type result_type;

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

Description

`impl` public member functions

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

Parameters:

`data`	A data of arbitrary type
`expr`	An expression
`state`	The current state

Returns:

proto::when<proto::_, Then-or-Else>()(expr, state, data)