[Haskell] Long live Edison

Iavor Diatchki iavor.diatchki at gmail.com
Mon Feb 20 20:10:02 EST 2006


On 2/20/06, John Meacham <john at repetae.net> wrote:
> I think the problem is that 'mzero' exists, the correct solution seems
> to be to get rid of the 'mzero' method of MonadPlus. Since haskell is
> lazy, all Monads have at least the zero of _|_ which can be overriden by
> 'fail' with a more suitable one. MonadPlus should be about extending
> monads with an additive operator, there is no need for another concept
> of zero and it seems to me that is the real issue. mzero can simply be
> defined as 'fail "mzero"'.

In what sense is _|_ a 'zero'?


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