I'll write this in PHP (where this thought originated), but this is generic to any object-orientated language. Basically, this is an addition to abstract classes that defines the implementation of its ...
Are there some theoretical reasons for that (like that the type checking or type inference would become undecidable), or practical reasons (too difficult to implement properly)? Currently, we can ...
One mandatory course I took in uni was about functional and logical programming languages (Haskell and Prolog). It was mildly interesting, and most I talked to showed even less interest to the course ...