readPGF :: FilePath -> IO PGF linearize :: PGF -> Language -> Tree -> String parse :: PGF -> Language -> Category -> String -> [Tree] linearizeAll :: PGF -> Tree -> [String] linearizeAllLang :: PGF -> Tree -> [(Language,String)] parseAll :: PGF -> Category -> String -> [[Tree]] parseAllLang :: PGF -> Category -> String -> [(Language,[Tree])] languages :: PGF -> [Language] categories :: PGF -> [Category] startCat :: PGF -> Category