[Haskell-beginners] [m [a]] -> m [a]

Guy guytsalmaves-h at yahoo.com
Wed Aug 17 14:05:43 CEST 2011


On 17/08/2011 14:32, Daniel Fischer wrote:
> On Wednesday 17 August 2011, 13:20:55, Guy wrote:
>> Is there a function which can do this, where m is not mplus?
>>
>> I would like all the lists to be joined inside the monad with ++.
>
> sequence gives you m [[a]], then an fmap concat (or liftM concat, since
> fmap requires an additional Functor constraint) flattens the resulting list
> to m [a].

Thanks. I was hoping that there would be some kind of fold that could do this; I take it there isn't one?




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