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where clause not in scope error

IK - TECHIK - TECH Posts: 14Member

Good day,
I am new to haskell and I am having difficulty compiling the following function definition

chaseFile :: [FilePath]          -- ^ path (directories to search)
          -> String              -- ^ base name
      -> [String]            -- ^ possible extensions
      -> IO String           -- ^ contents of file
chaseFile dirs basename exts
  = do results <- mapM tryReadFile fnames
       case dropWhile hasFailed results of
         ((Right (fc,fn)):_)
         -> errLn ("Read file: "++fn) >> return fc
     _   -> errLn ("Could not find file: "++basename) >> mzero
      fnames = [d++'/':basename++'.':e | d <- dirs, e <- exts]
      hasFailed (Left _) = True
      hasFailed _        = False
      tryReadFile fn = try ( readFile fn >>= \fc -> return (fc,fn) )

The compiler gives the following error
*** Parser:
*** Renamer/typechecker:
Not in scope: 'try'

Thanks in anticiption

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