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Re: "validating" map for collections

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adriaanm
Joined: 2010-02-08,
User offline. Last seen 31 weeks 4 days ago.
as an aside: one of the nice side-effects (haha) about using implicits to implement type classes is that you can provide the dictionary explicitly when needed
hence, mapM and map (specialised for the List monad) can be the same method in Scala (I think we briefly mention this in our paper "Type Classes as Objects and Implicits"). To some extent, this is related to breakOut in the actual collection library, which lets you break out from one monad (errr, collection) to another

adriaan
On Thu, Feb 24, 2011 at 9:53 AM, Sadek Drobi <sadek [dot] drobi [at] gmail [dot] com> wrote:
Thank you Tony. I know actually about Monads don't compose part. What I was referring to is "Since Scala always operates in the Identity monad, there is no need for a transformer"
Sadek

On Thu, Feb 24, 2011 at 2:33 AM, Tony Morris <tonymorris [at] gmail [dot] com> wrote:
On 24/02/11 10:00, Sadek Drobi wrote:
> Can you please clarify to me this sentence?

Hi mate, I've given it a shot mate on my blog. This can get hairy but
hope it helps!
http://blog.tmorris.net/monads-do-not-compose/



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