Peter Dimov wrote:
David Bergman wrote:
On the meta level, a trait places a Concept in relation to other Concepts, i.e., a trait is STRUCTURAL. On the object-level,
a Model is
related to other Models or Features.
trait<Type>::neighbor_type - relates two Concepts trait<Type>::child_type - adds a Feature
A policy is BEHAVIORAL. And one often uses policies in a dynamic setting, adding them in runtime. We, of course, often implicitly refer to the compile-time policies...
So...
In A<X>::frobnicate(), 'A' is a policy, because it's behavioral, and in
No, A is not behavioral. The feature "frobnicate" of the type X is. And, that mapped behaviors can definitely be used as a policy.
template<class B> struct X { template typename B::value_type value_type; };
'B' is a trait, because it's structural?
No, since a trait not only has to be structural, but *also* be a (set of) meta functions with the Concept as a range. /David