boost::bimaps::relation::member_at Namespace Reference

member_at::side idiom to access relation values and types using metaprogramming. More...

Classes
struct	info
	Member info tag. More...
struct	left
	Member at left tag. More...
struct	right
	Member at right tag. More...

Detailed Description

member_at::side idiom to access relation values and types using metaprogramming.

This tags are used to specify which member you want to acces when using a metafunction over a symmetrical type. The idea is to be able to write code like:

result_of::get<member_at::left,relation>::type data = get<member_at::left>(rel);

The relation class supports this idiom even when the elements are tagged. This is useful because a user can decide to start tagging in any moment of the development.

See also member_with_tag, is_tag_of_member_at_left, is_tag_of_member_at_right, get value_type_of, pair_by, pair_type_by.