Hello,
see http://en.wikipedia.org/wiki/Type_class I have tried several times to express the idea of using intervaces (only) for template case selection. Instead of a combination of really penible & hardly readible is() expressions and adhoc functions like isRandomAccessRange. (No chance in these trials ;-) Just discovered this idea is actually the same as 'type classes' introduced in Haskell (not that I'm a fan of functional programming, just stepped on the article by chance). D does not need any new language feature: interfaces are perfect for that. Maybe the syntax could be slightly extended to allow expressing negative constraints, like the following (defining an interface for types that support '==', but not comp) interface EqualityOnly : Equality !: Comparable {} Denis -- -- -- -- -- -- -- vit esse estrany ☣ spir.wikidot.com
