[Haskell-beginners] Re: data constructors

[Sterling Clover]

Maybe just bikeshedding here (and on -beginners, no less), but this  
seems like a job for Data.Traversable.sequence?

sequence :: Monad m => t (m a) -> m (t a)

Cheers,
S.

On Apr 20, 2009, at 3:00 AM, Heinrich Apfelmus wrote:
>
> Functors sounds good to me.
>
>    data Named a = N Name a
>    data Timed a = T Time a
>
>    instance Functor Named where ...
>    instance Functor Timed where ...
>
>    convert :: Named [Timed Chord] -> Timed [Named Chord]
>
>
> Bu you can also use plain type synonyms
>
>    type Named a = (Name,a)
>    type Timed a = (Time,a)
>
> and write your own record selectors by hand
>
>    name :: Named a -> Name
>    name = fst
>
>    time :: Timed a -> Time
>    time = fst
>
>    value :: (b,a) -> a
>    value = snd
>
>
>
> Regards,
> apfelmus
>
> --
> http://apfelmus.nfshost.com
>
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