[Haskell-cafe] A question about "monad laws"

Dan Piponi dpiponi at gmail.com
Mon Feb 11 13:09:39 EST 2008

IOn Feb 11, 2008 9:46 AM, Miguel Mitrofanov <miguelimo38 at yandex.ru> wrote:
> It's well known that "ListT m" monad violates this law in general
> (though it satisfies it for some particular monads m). For example,

I went through this example in quite a bit of detail a while ago and
wrote it up here:
http://sigfpe.blogspot.com/2006/11/why-isnt-listt-monad.html . I tried
to show not just why the monad laws fails to hold for ListT [], but
also show how it almost holds.

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