[Haskell-cafe] Re: what is inverse of mzero and return?

Aaron Denney wnoise at ofb.net
Sun Jan 23 05:07:27 EST 2005

On 2005-01-23, Keean Schupke <k.schupke at imperial.ac.uk> wrote:
> Is there only on correct definition of a monad/monoid on lists - or does 
> anything that satisfies the monad laws count? I got the impression you 
> could define anthing you liked for mzero and mplus - providing the laws 
> are upheld?

You can, but the "other one" turns it into a copy of the Maybe Monad, so
the current one is more useful.

Aaron Denney

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