In Scala we can define the type-level identity function for lower-kinded types like so, type Id[A] = A
We know that implementing classes are still invariant, despite the fact that their interfa开发者_如何学编程ces are variant. However I am inquiring, is cov/contravariance a step closer to parametric po
Suppose one wants to build a novel generic class, Novel[A].This class will contain lots of useful methods--perhaps it is a type of collection--and therefore you want to subclass it.But you want the me
This question is for the people who know both Haskell (or any other functional language that support开发者_开发百科s Higher-kinded Types) and C++...
In this declaration data Const a = Const Integer Haskell infers that Const is * -> *. Is it possible to make Const take a type constructor instead, so it will be (* -> *) -> *? Idea开发者_
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