[Haskell-beginners] Indenting
Brent Yorgey
byorgey at seas.upenn.edu
Sat Dec 5 11:35:03 EST 2009
On Fri, Dec 04, 2009 at 08:26:52PM +0000, John Moore wrote:
>
> type Indent = (Int)
> spacing :: Int -> Indent
> spacing n = Nothing
> spacing n (x:xs) = if (n==1)
> then (Just n)
> else spacing n xs
> where (n > 1)
Hmm, you seem to be a bit confused. What exactly is spacing supposed
to do? What is its type? Your type signature says that it has type
Int -> Int, but the second equation spacing n (x:xs) = ... suggests
that it takes TWO arguments, with the second being a list of some
sort; also, it seems to be returning things of type Maybe Int
(Nothing, Just n). So, what is it supposed to do? Is it computing an
*amount* of indentation? Is it supposed to take a String and put
spaces on the front? or...?
-Brent
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