[Haskell-beginners] flip lookup in ghci

Matt R mattrussell324 at googlemail.com
Fri Feb 20 07:44:30 EST 2009


Rafael Gustavo da Cunha Pereira Pinto <RafaelGCPP.Linux at gmail.com>:
> you are applying the type to lookup only!
>
> try let lookupIn = ((flip lookup ) :: (Eq a) => [(a, b)] -> a -> Maybe b )

Oops, I didn't mean to include my attempts at type annotation in my
previous email...I meant to write

ghci> let lookupIn = flip lookup

But it doesn't seem to make any difference either way. I still get

ghci> :t lookupIn
lookupIn :: [((), b)] -> () -> Maybe b

regardless :(

-- Matt


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