transformers versus mtl

[Brandon S. Allbery KF8NH]

On 2009 Mar 24, at 20:36, Alexander Dunlap wrote:
> I'm pretty sure all monads are functors.

All monads are functors, but IIRC not all Monads are Functors.  But  
Monad includes a liftM which is the same as Functor's fmap (usually?  
something tickling me about possibly the list Monad?) so in fact you  
*could* synthesize a Functor from atop a Monad that isn't already a  
Functor.

-- 
brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university    KF8NH


-------------- next part --------------
A non-text attachment was scrubbed...
Name: PGP.sig
Type: application/pgp-signature
Size: 195 bytes
Desc: This is a digitally signed message part
Url : http://www.haskell.org/pipermail/libraries/attachments/20090324/a736a1dd/PGP.bin