Sorry; forgot to CC the list
That case is equivalent to:
if filex
then return $ Just $ file x
else if filex'
then return $ Just $ file' x
else findHelper xs
The specific syntax being used is called a "pattern guard":
http://www.haskell.org/haskellwiki/Pattern_guard
On Tue, Dec 8, 2009 at 16:59, zaxis
findHelper (x:xs) = do -- not lazy, but that's not really important here filex <- fileExists (file x) filex' <- fileExists (file' x) case () of _ | filex -> return $ Just $ file x | filex' -> return $ Just $ file' x | otherwise -> findHelper xs file x = foldl1 joinFileName (x ++ [helper]) file' x = (file x) ++ (getConfig "exe_ext")
Sincerely!
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