[Haskell-cafe] do/if/then/else confusion

[David Carter]

Another newbie question, but I can't seem to find any answers on the web...

Can someone tell me what's wrong with this?

import qualified System.Posix.Directory as PD

readdirAll :: PD.DirStream -> IO [String]
readdirAll d =
   do dir <- PD.readDirStream d
      if dir == ""
        then return []
        else rest <- readdirAll d
             return (dir:rest)

Compiling with GHC 6.6.1 gives me the not-very-useful message "Parse 
error in pattern", pointing to the "i" of "if". I've tried all kinds of 
alternative indentations (including indenting the "else" more), 
bracketings etc, but nothing helps.

Thanks

David



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