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Struct template make_expr

boost::proto::result_of::make_expr — Metafunction that computes the return type of the proto::make_expr() function, with a domain deduced from the domains of the children.


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

template<typename Tag, typename... A> 
struct make_expr {
  // types
  typedef domain-deduced-from-child-types D;
  typedef typename proto::result_of::make_expr<Tag, D, A...>::type type;


Computes the return type of the proto::make_expr() function.

In this specialization, the domain is deduced from the domains of the child types. If proto::is_domain<A0>::value is true, then another specialization is selected.

make_expr public types

  1. typedef domain-deduced-from-child-types D;

    For each x in [0,N) (proceeding in order beginning with x=0), if proto::domain_of<Ax>::type is not proto::default_domain, then D is proto::domain_of<Ax>::type. Otherwise, D is proto::default_domain.