On 7/15/07, Miguel Mitrofanov <[EMAIL PROTECTED]> wrote:
SOR> I've heard that Monads are in some way like Monoids, hence the
SOR> name. But I don't understand the explanation yet myself :(
Just compare:
Monoid: a set M with maps ident: M^0 -> M and product: M^2 -> M
(here M^0 is a one-element set)
Monad: a functor M with natural transformations return: M^0 -> M and
join: M^2 -> M
(here M^0 is an identity functor)
I had forgotten that the identity element was from M^0 -> M. In my gut I
always feel it should be something more like M -> M, though I realize (as
Stefan pointed out) I'm thinking too much in set-terms and not in
category-terms.
David
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