From 4803fb8052caba0421949c9d7768d44ec28d109d Mon Sep 17 00:00:00 2001 From: "kr.angelov" Date: Thu, 5 Jun 2008 07:33:42 +0000 Subject: use parser combinators to parse the shell commands. simplified CommandLine type --- src-3.0/GF/Command/Parse.hs | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 src-3.0/GF/Command/Parse.hs (limited to 'src-3.0/GF/Command/Parse.hs') diff --git a/src-3.0/GF/Command/Parse.hs b/src-3.0/GF/Command/Parse.hs new file mode 100644 index 000000000..e3cc21cca --- /dev/null +++ b/src-3.0/GF/Command/Parse.hs @@ -0,0 +1,35 @@ +module GF.Command.Parse(readCommandLine) where + +import PGF.ExprSyntax +import GF.Command.Abstract + +import Data.Char +import qualified Text.ParserCombinators.ReadP as RP + +readCommandLine :: String -> Maybe CommandLine +readCommandLine s = case [x | (x,cs) <- RP.readP_to_S pCommandLine s, all isSpace cs] of + [x] -> Just x + _ -> Nothing + +test s = RP.readP_to_S pCommandLine s + +pCommandLine = RP.sepBy (RP.skipSpaces >> pPipe) (RP.skipSpaces >> RP.char ';') + +pPipe = RP.sepBy (RP.skipSpaces >> pCommand) (RP.skipSpaces >> RP.char '|') + +pCommand = do + cmd <- pIdent + RP.skipSpaces + opts <- RP.many pOption + arg <- RP.option ANoArg (fmap AExp (pExp False)) + return (Command cmd opts arg) + +pOption = do + RP.char '-' + flg <- pIdent + RP.option (OOpt flg) (fmap (OFlag flg) (RP.char '=' >> pValue)) + +pValue = do + fmap VId pIdent + RP.<++ + fmap (VInt . read) (RP.munch1 isDigit) -- cgit v1.2.3