[Haskell-cafe] fmap vs. liftM

Brandon S. Allbery KF8NH allbery at ece.cmu.edu
Tue Feb 5 08:57:33 EST 2008


On Feb 5, 2008, at 8:31 , Henning Thielemann wrote:

> How do you convince the compiler that
>   'join (fmap return x) == x' ?

How do you convince it that the current formulation of Monad obeys  
the monad laws?  (rhetorical)

-- 
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




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