[Haskell-beginners] Type classes and synonyms
Philip Scott
haskell-beginners at foo.me.uk
Sat Nov 21 12:39:20 EST 2009
Hi Stephan,
> > instance Num a => Num [a] where
> > (+) = zipWith (+)
> > (-) = zipWith (-)
> > (*) = zipWith (*)
> > fromInteger = repeat . fromInteger
> > abs = map abs
> > signum = map signum
Oooh I had no idea you could do that with 'instance'
I merge my lists into a list of pairs before I do anything with them so
unevenness isn't a problem; I was just trying t convince haskell that I could
use nice operators like '+' on my derived type.
Thank you very much for your reply; between that and Felipe's I have enough to
keep me busy all evening digesting the new toys you have demonstrated :)
- Philip
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