> Actually, that was my starting point. However, this approach does not > scale up: > > A concept typically is a collection of requirements that have to be met > individually. A huge boolean statement inside an assertion does not give > any clue as to which part of it failed. > > The isXxx approach works fine for the template constraint itself, but to > assert that a given type meets all requirements of a concept, it is not > very usable at all.
Wouldn't it be preferable to improve the compiler to a degree, that it can tell, which subexpression of a constraint failed?
