[Haskell-cafe] getting last char of String

[Jesse Schalken]

On Sat, Jan 1, 2011 at 8:54 AM, Felipe Almeida Lessa <felipe.lessa at gmail.com
> wrote:

> On Fri, Dec 31, 2010 at 6:43 PM, aditya siram <aditya.siram at gmail.com>
> wrote:
> > -- untested and won't work on an infinite list
> > last :: [a] -> a
> > last = head . reverse
>
> No definition for last works with infinite lists =).


Unless you make the result nullable, of course.

maybeLast :: [a] -> Maybe a


maybeLast [] = Nothing

maybeLast [x] = Just x
maybeLast (_:xs) = maybeLast xs


> Cheers,
>
> --
> Felipe.
>
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