[Haskell-beginners] homogeneous value list

[Ozgur Akgun]

Another boring variant from me then.

isHomogeneous xs = all (first==) xs
    where first = head xs

Guess what? You do not need the special case for [], because "all _ [] =
True" allways. So if the list is empty, it won't even try evaluating
"first".

Cheers,

On 12 March 2010 14:08, Daniel Fischer <daniel.is.fischer at web.de> wrote:

> Am Freitag 12 März 2010 14:41:11 schrieb Daniel Fischer:
> >
> > isHomogeneous :: Eq a => [a] -> Bool
> > isHomogeneous [] = True
> > isHomogeneous (x:xs) = all (== x) xs
> >
>
> Variant, getting rid of the special case for an empty list:
>
> isHomogeneous :: Eq a => [a] -> Bool
> isHomogeneous xs = and (zipWith (==) xs (drop 1 xs))
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-- 
Ozgur Akgun
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