[Haskell-cafe] Missing Symbol (2)
Thomas Hartman
thomas.hartman at db.com
Wed Sep 19 10:04:40 EDT 2007
as provided, this won't compile because v hasn't been defined.
f [] = 0
f (x:xs) = x . f xs
compiles but gives
f :: (Num (a -> c)) => [c -> c] -> a -> c
which seems wrong. maybe I'm not understanding what v is not supposed to
be.
I am thinking maybe you want iterate
*Main> take 5 $ iterate (+1) 0
[0,1,2,3,4]
It would be easier to understand your desired function if you would
provide an example of desired usage.
t.
PR Stanley <prstanley at ntlworld.com>
Sent by: haskell-cafe-bounces at haskell.org
09/19/2007 02:17 AM
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[Haskell-cafe] Missing Symbol (2)
Hi
Here's another one:
f [] = v
f (x:xs) = x . f xs
The "." is supposed to denote a generic operator - f [] maps to some
value v and applied to non-empty list applies head to ? operator.
Thanks, Paul
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