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

Keean Schupke k.schupke at imperial.ac.uk
Mon Jan 24 04:36:12 EST 2005


Ashley Yakeley wrote:

>
>I disagree. Clearly (putStrLn "Hello" >> mzero) is not the same as mzero.
>
>  
>
Yes it is, side effects are quite clearly not counted. The value
of (putStrLn "Hello" >> mzero") is mzero.

In reference to the idea of splitting MonadPlus, what category
would you be operating in, if you have a zero but no co-product
operation?

    Keean.


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