[Haskell-beginners] Parse error in pattern
magnus at therning.org
Fri Feb 26 11:37:30 EST 2010
It doesn't look like a complete piece of code so these comments aren't
backed up by running it through GHCi or anything.
On Fri, Feb 26, 2010 at 16:29, Florian Duret <flo.morphe at gmail.com> wrote:
> I try to set up a verification on the number of arguments given to my
> program, but keep on getting "Parse error in pattern"
> Here is what my code looks like:
> main :: IO()
> main = do
> -- On commence par ouvrir le fichier SAC en mode binaire
> argsList <- getArgs
> if (length (argsList) == 0)
> then do
> putStrLn $ "No filename given to the program.\n $ ProgramName
> return ()
I believe the 'do' here is unecessary.
> sacFile1 <- openBinaryFile fileToOpen ReadMode
Here you do need a 'do' though, I believe.
> ghci complains, and tells "Parse error in pattern", indicating the 'if' line
> Can you please help ?
> Thank you very much,
> Beginners mailing list
> Beginners at haskell.org
Magnus Therning (OpenPGP: 0xAB4DFBA4)
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