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

Ketil Malde ketil+haskell at ii.uib.no
Tue Jan 25 02:32:48 EST 2005

Daniel Fischer <daniel.is.fischer at web.de> writes:

>> 'everything matters' is wrong even for IO actions, because the
>> actual value returned when the action is executed is completely
>> irrelevant to the IO action's identity.

> Now that I cannot swallow, that would mean
> return 4 == return 5.

I would argue that 'return 4' (or '5') isn't an IO action (it may not
even be in the IO monad, of course, but even within it.)

If I haven't seen further, it is by standing in the footprints of giants

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