Boost C++ Libraries Home Libraries People FAQ More

PrevUpHomeNext

Struct template callable_eval

boost::proto::context::callable_eval — A BinaryFunction that accepts a Proto expression and a callable context and calls the context with the expression tag and children as arguments, effectively fanning the expression out.

Synopsis

// In header: <boost/proto/context/callable.hpp>

template<typename Expr, typename Context> 
struct callable_eval {
  // types
  typedef  ;

  // public member functions
   (, ) ;
};

Description

proto::context::callable_eval<> requires that Context is a PolymorphicFunctionObject that can be invoked with Expr's tag and children as expressions, as follows:

proto::child_c<proto::child_c<

callable_eval public member functions

  1.  ( expr,  context) ;

    Parameters:

    context

    The callable evaluation context

    expr

    The current expression

    Returns:

    context(typename Expr::proto_tag(), proto::child_c<0>(expr),... proto::child_c<N>(expr))


PrevUpHomeNext