create type class syntax

[aripiprazole]

Create the type class, and constraint syntax:

class Monad m =
  pure : Ɐ a. a -> m a
  (>>=) : Ɐ a b. m a -> (a -> m b) -> m b 

And the constraint syntax:

instance Monad (List Int) = ...

using : List String
using = [1, 2, 3] >>= (+ 1)