PROPOSAL: Make Applicative a superclass of Monad

Ross Paterson ross at
Tue Jun 24 07:48:38 EDT 2008

On Tue, Jun 24, 2008 at 01:43:08PM +0200, Christian Maeder wrote:
> Could someone explain why it breaks H98 compatibility?  
> Control.Applicative alone is at least marked "portable".

The following Haskell 98 code would be rejected:

newtype Id a = Id a

instance Monad Id where
	return = Id
	Id x >>= f = f x

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