[Haskell-beginners] Re: mind your head, was: Parsing a file with data divided into sections

[Magnus Therning]

On Fri, Feb 6, 2009 at 10:30 AM, Christian Maeder
<Christian.Maeder at dfki.de> wrote:
[..]
>> Another course of action would be to add exception handling; if head
>> throws an exception then the input file isn't following the accepted
>> syntax.
>
> I'ld rather check all lines before (or filter non empty ones) than
> trying to catch Prelude.head: empty list!

Yes, that's how I modified my own "solution" once I tracked down what
sort of input it would fail on:

    main = interact (unlines . map show . countDays . dropWhile null . lines)

/M

-- 
Magnus Therning                        (OpenPGP: 0xAB4DFBA4)
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