[Haskell-cafe] From monads to monoids in a small category

[Alberto G. Corona]

Not to mention the ugly formatting ;)

2012/9/5 Richard O'Keefe <ok at cs.otago.ac.nz>:
>
> On 4/09/2012, at 10:39 PM, Alberto G. Corona wrote:
>
>> "Monads are monoids in the category of endofunctors"
>>
>> This Monoid instance for the endofunctors of the set of all  elements
>> of (m a)   typematch in Haskell with FlexibleInstances:
>>
>> instance Monad m => Monoid  (a -> m a) where
>>   mappend = (>=>)   -- kleisly operator
>>   mempty  = return
>>
>> The article can be found here:
>>
>> http://haskell-web.blogspot.com.es/2012/07/from-monads-to-monoids-in-small.html
>>
>> I would appreciate some comments.
>
> s/kleisly/Kleisli/
> In the article,
> s/Lets/Let's/
> /Here 'm b' as/ s/as/is/
> s/this_are/this are/
> s/first, is/first is/
> s/haskell/Haskell/
> s/polimorphic/polymorphic/
> s/x=/x =/
> s/let's/Let's/
> s/condition, associativity/condition, associativity,/
> /if not where that way, .* guess/
>         I *think* you mean to say something like
>         (If it were not so, it would be impossible to
>         define the denotational semantics of imperative
>         languages in terms of monads, I guess.)
> Generally, it's "according TO", not "according WITH",
> and "associated WITH", not "associated TO".
>
> instance Functor a
>         doesn't seem to be legal Haskell.
>
> At this point I stopped reading.
>
>