[Haskell-cafe] Syntax of 'do'

David House dmhouse at gmail.com
Fri Aug 29 11:07:48 EDT 2008

2008/8/29 Maurí­cio <briqueabraque at yahoo.com>:
> x :: Prelude.Monad a
> y :: Prelude.Monad b
> foo :: b -> Prelude.Monad c

Monad is not a type, it is a type class, so you probably mean:

x :: Monad m => m a
y :: Monad m => m b
foo :: Monad m => b -> m c

With the further understanding that all three `m's must be the same.


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