now the abstract syntax in PGF allows the same syntax for integers, floats and strings as in Haskell. This includes negative integers and exponents in the floats

src/compiler/GF/Command/Parse.hs

@@ -39,9 +39,9 @@ pOption = do
   RP.option (OOpt flg) (fmap (OFlag flg) (RP.char '=' >> pValue))
 
 pValue = do
-  fmap (VInt . read) (RP.munch1 isDigit)
+  fmap VInt (RP.readS_to_P reads)
   RP.<++
-  fmap VStr pStr
+  fmap VStr (RP.readS_to_P reads)
   RP.<++
   fmap VId  pFilename
 

src/runtime/haskell/PGF/Expr.hs

@@ -15,7 +15,7 @@ module PGF.Expr(Tree, BindType(..), Expr(..), Literal(..), Patt(..), Equation(..
                 MetaId,
 
                 -- helpers
-                pMeta,pStr,pArg,pLit,freshName,ppMeta,ppLit,ppParens
+                pMeta,pArg,pLit,freshName,ppMeta,ppLit,ppParens
                ) where
 
 import PGF.CId
@@ -194,16 +194,11 @@ pMeta = do RP.char '?'
            return 0
 
 pLit :: RP.ReadP Literal
-pLit = pNum RP.<++ liftM LStr pStr
-
-pNum = do x <- RP.munch1 isDigit
-          ((RP.char '.' >> RP.munch1 isDigit >>= \y -> return (LFlt (read (x++"."++y))))
-           RP.<++
-           (return (LInt (read x))))
-
-pStr = RP.char '"' >> (RP.manyTill (pEsc RP.<++ RP.get) (RP.char '"'))
-       where
-         pEsc = RP.char '\\' >> RP.get    
+pLit = liftM LStr (RP.readS_to_P reads)
+       RP.<++
+       liftM LInt (RP.readS_to_P reads)
+       RP.<++
+       liftM LFlt (RP.readS_to_P reads)
 
 
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