Struct template child

boost::proto::result_of::child — A metafunction that returns the type of the N^th child of a Proto expression, where N is an MPL Integral Constant.

Synopsis

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

template<typename Expr, typename N = mpl::long_<0> > 
struct child :  proto::result_of::child_c<Expr, N::value> {
};

Description

proto::result_of::child<Expr, N> is equivalent to proto::result_of::child_c<Expr, N::value>.