made -fcfg default parser; added lexer textvars

doc/gf-history.html

@@ -12,6 +12,16 @@ Changes in functionality since May 17, 2005, release of GF Version 2.2
 
 </center>
 
+<p>
+
+20/6 (AR) The FCFG parser is know the default, as it even handles literals.
+The old default can be selected by <tt>p -old</tt>. Since
+FCFG does not support variable bindings, <tt>-old</tt> is automatically
+selected if the grammar has bindings - and unless the <tt>-fcfg</tt> flag
+is used.
+
+<p>
+
 17/6 (AR) The FCFG parser is now the recommended method for parsing
 heavy grammars such as the resource grammars. It does not yet support
 literals and variable bindings.

src/GF/Compile/ShellState.hs

@@ -188,6 +188,10 @@ stateOptions   = loptions
 stateGrammarWords = allMorphoWords . stateMorpho
 stateGrammarLang st = (grammar st, cncId st)
 
+---- this should be computed at compile time and stored
+stateHasHOAS :: StateGrammar -> Bool
+stateHasHOAS = hasHOAS . stateGrammarST
+
 cncModuleIdST :: StateGrammar -> CanonGrammar
 cncModuleIdST = stateGrammarST
 

src/GF/Grammar/LookAbs.hs

@@ -21,6 +21,7 @@ module GF.Grammar.LookAbs (GFCGrammar,
 		lookupRef,
 		refsForType,
 		funRulesOf,
+		hasHOAS,
 		allCatsOf,
 		allBindCatsOf,
 		funsForType,
@@ -130,6 +131,10 @@ funRulesOf gr =
                  mtype m == MTAbstract,
                  (f, C.AbsFun typ _) <- tree2list (jments m)]
 
+-- testing for higher-order abstract syntax
+hasHOAS :: GFCGrammar -> Bool
+hasHOAS gr = any isHigherOrderType [t | (_,t) <- funRulesOf gr] where
+
 allCatsOf :: GFCGrammar -> [(Cat,Context)]
 allCatsOf gr = 
   [((i,c),cont) | (i, ModMod m) <- modules gr,

src/GF/Grammar/Macros.hs

@@ -136,6 +136,10 @@ isRecursiveType t = errVal False $ do
   (cc,c) <- catSkeleton t -- thus recursivity on Cat level
   return $ any (== c) cc
 
+isHigherOrderType :: Type -> Bool
+isHigherOrderType t = errVal True $ do  -- pessimistic choice
+  co <- contextOfType t
+  return $ not $ null [x | (x,Prod _ _ _) <- co]
 
 contextOfType :: Type -> Err Context
 contextOfType typ = case typ of

src/GF/Shell/HelpFile.hs

@@ -212,12 +212,12 @@ txtHelpFile =
   "\n      -fail      show strings whose parse fails prefixed by #FAIL" ++
   "\n      -ambiguous show strings that have more than one parse prefixed by #AMBIGUOUS" ++
   "\n  options for selecting parsing method:" ++
-  "\n      (default)parse using an overgenerating CFG" ++
+  "\n      -fcfg    parse using a fast variant of MCFG (default is no HOAS in grammar)" ++
+  "\n      -old     parse using an overgenerating CFG (default if HOAS in grammar)" ++
   "\n      -cfg     parse using a much less overgenerating CFG" ++
   "\n      -mcfg    parse using an even less overgenerating MCFG" ++
-  "\n      -fcfg    parse using a faster variant of MCFG" ++
+  "\n      Note:    the first time parsing with -cfg, -mcfg, and -fcfg may take a long time" ++
-  "\n      Note:    the first time parsing with -cfg, -mcfg, and -fcfg might take a long time" ++
+  "\n  options that only work for the -old default parsing method:" ++
-  "\n  options that only work for the default parsing method:" ++
   "\n      -n       non-strict: tolerates morphological errors" ++
   "\n      -ign     ignore unknown words when parsing" ++
   "\n      -raw     return context-free terms in raw form" ++
@@ -594,6 +594,7 @@ txtHelpFile =
   "\n    -lexer=chars         each character is a token" ++
   "\n    -lexer=code          use Haskell's lex" ++
   "\n    -lexer=codevars      like code, but treat unknown words as variables, ?? as meta " ++
+  "\n    -lexer=textvars      like text, but treat unknown words as variables, ?? as meta " ++
   "\n    -lexer=text          with conventions on punctuation and capital letters" ++
   "\n    -lexer=codelit       like code, but treat unknown words as string literals" ++
   "\n    -lexer=textlit       like text, but treat unknown words as string literals" ++

src/GF/Shell/ShellCommands.hs

@@ -184,8 +184,9 @@ optionsOfCommand co = case co of
   CTransformGrammar _ -> flags "printer"
   CConvertLatex _ -> none
   CLinearize _ -> both "utf8 table struct record all multi" "lang number unlexer mark"
-  CParse -> both "ambiguous fail cut new newer cfg mcfg fcfg n ign raw v lines all prob" 
+  CParse -> 
-                 "cat lang lexer parser number rawtrees"
+    both "ambiguous fail cut new newer old cfg mcfg fcfg n ign raw v lines all prob" 
+         "cat lang lexer parser number rawtrees"
   CTranslate _ _ -> opts "cat lexer parser"
   CGenerateRandom -> both "cf prob" "cat lang number depth atoms noexpand doexpand"
   CGenerateTrees -> both "metas" "atoms depth alts cat lang number noexpand doexpand"

src/GF/UseGrammar/Custom.hs

@@ -450,6 +450,7 @@ customTokenizer =
   ,(strCI "chars",     const $ sg . map (tS . singleton))
   ,(strCI "code",      const $ sg . lexHaskell)
   ,(strCI "codevars",  \gr -> sg . (lexHaskellVar $ stateIsWord gr))
+  ,(strCI "textvars",  \gr -> sg . (lexTextVar $ stateIsWord gr))
   ,(strCI "text",      const $ sg . lexText)
   ,(strCI "unglue",    \gr -> sg . map tS . decomposeWords (stateMorpho gr))
   ,(strCI "codelit",   \gr -> sg . (lexHaskellLiteral $ stateIsWord gr))

src/GF/UseGrammar/Parsing.hs

@@ -54,34 +54,9 @@ parseStringMsg os sg cat s = do
   return (ts, unlines $ reverse ss)
 
 parseStringC :: Options -> StateGrammar -> CFCat -> String -> Check [Tree]
-
+parseStringC opts0 sg cat s 
----- to test peb's new parser 6/10/2003
+ | oElem (iOpt "old") opts0 ||
----- (obsoleted by "newer" below)
+   (not (oElem (iOpt "fcfg") opts0) && stateHasHOAS sg) = do
--- parseStringC opts0 sg cat s
---  | oElem newParser opts0 = do  
---   let pm = maybe "" id $ getOptVal opts0 useParser -- -parser=pm
---       ct = cfCat2Cat cat
---   ts <- checkErr $ NewOld.newParser pm sg ct s
---   mapM (checkErr . annotate (stateGrammarST sg) . refreshMetas []) ts
-
--- to use peb's newer parser 7/4-05 
-parseStringC opts0 sg cat s
- | oElem newCParser opts0 || oElem newMParser opts0 || oElem newFParser opts0 || oElem newParser opts0 || oElem newerParser opts0 = do  
-  let opts      = unionOptions opts0 $ stateOptions sg
-      algorithm | oElem newCParser opts0 = "c"
-		| oElem newMParser opts0 = "m"
-		| oElem newFParser opts0 = "f"
-		| otherwise              = "c" -- default algorithm
-      strategy  = maybe "bottomup" id $ getOptVal opts useParser -- -parser=bottomup/topdown
-      tokenizer = customOrDefault opts useTokenizer customTokenizer sg
-      toks = case tokenizer s of
-               t:_ -> t
-               _ -> [] ---- no support for undet. tok.
-  ts <- checkErr $ New.parse algorithm strategy (pInfo sg) (absId sg) cat toks
-  ts' <- mapM (checkErr . annotate (stateGrammarST sg) . refreshMetas []) ts
-  return $ optIntOrAll opts flagNumber ts'
-
-parseStringC opts0 sg cat s = do
   let opts = unionOptions opts0 $ stateOptions sg
       cf  = stateCF sg
       gr  = stateGrammarST sg
@@ -92,6 +67,26 @@ parseStringC opts0 sg cat s = do
     then doUntil (not . null) $ map (tokens2trms opts sg cn parser) toks
     else mapM (tokens2trms opts sg cn parser) toks >>= return . concat
 
+---- | or [oElem p opts0 | 
+----        p <- [newCParser,newMParser,newFParser,newParser,newerParser] = do  
+
+ | otherwise = do
+  let opts      = unionOptions opts0 $ stateOptions sg
+      algorithm | oElem newCParser opts0 = "c"
+		| oElem newMParser opts0 = "m"
+		| oElem newFParser opts0 = "f"
+		| otherwise              = "f" -- default algorithm: FCFG
+      strategy  = maybe "bottomup" id $ getOptVal opts useParser 
+                      -- -parser=bottomup/topdown
+      tokenizer = customOrDefault opts useTokenizer customTokenizer sg
+      toks = case tokenizer s of
+               t:_ -> t
+               _ -> [] ---- no support for undet. tok.
+  ts <- checkErr $ New.parse algorithm strategy (pInfo sg) (absId sg) cat toks
+  ts' <- mapM (checkErr . annotate (stateGrammarST sg) . refreshMetas []) ts
+  return $ optIntOrAll opts flagNumber ts'
+
+
 tokens2trms :: Options ->StateGrammar ->Ident -> CFParser -> [CFTok] -> Check [Tree]
 tokens2trms opts sg cn parser toks = trees2trms opts sg cn toks trees info
     where result = parser toks

src/GF/UseGrammar/Tokenize.hs

@@ -20,6 +20,7 @@ module GF.UseGrammar.Tokenize ( tokWords,
 		  lexHaskellLiteral,
 		  lexHaskellVar,
 		  lexText,
+		  lexTextVar,
 		  lexC2M, lexC2M',
 		  lexTextLiteral,
                   lexIgnore,
@@ -58,6 +59,10 @@ isFloat s = case s of
   '.':cs@(_:_)     -> all isDigit cs
   _ -> False
 
+isString s = case s of
+  c:cs@(_:_) -> (c == '\'' && d == '\'') || (c == '"' && d == '"') where d = last cs
+  _ -> False
+
 
 mkCFTok :: String -> CFTok
 mkCFTok s = case s of
@@ -86,6 +91,7 @@ mkLit s
   | all isDigit s = tI s
   | otherwise = tL s
 
+-- obsolete
 mkTL :: String -> CFTok
 mkTL s 
   | isFloat s = tF s
@@ -104,6 +110,7 @@ lexText :: String -> [CFTok]
 lexText = uncap . lx where
 
   lx s = case s of
+    '?':'?':cs          -> tS "??" : lx cs
     p : cs | isMPunct p -> tS [p] : uncap (lx cs)
     p : cs | isPunct p  -> tS [p] : lx cs
     s : cs | isSpace s  -> lx cs
@@ -177,7 +184,7 @@ unknown2string isKnown = map mkOne where
     | isFloat s = tF s
     | all isDigit s = tI s 
     | otherwise = tL s
-  mkOne t@(TC s) = if isKnown s then t else mkTL s
+  mkOne t@(TC s) = if isKnown s then t else mkLit s
   mkOne t        = t
 
 unknown2var :: (String -> Bool) -> [CFTok] -> [CFTok]
@@ -186,6 +193,7 @@ unknown2var isKnown = map mkOne where
   mkOne t@(TS s) 
     | isKnown s = t
     | isFloat s = tF s
+    | isString s = tL (init (tail s))
     | all isDigit s = tI s 
     | otherwise = tV s
   mkOne t@(TC s) = if isKnown s then t else tV s
@@ -197,6 +205,8 @@ lexTextLiteral    isKnown = unknown2string (eitherUpper isKnown) . lexText
 lexHaskellLiteral isKnown = unknown2string isKnown . lexHaskell
 
 lexHaskellVar     isKnown = unknown2var isKnown . lexHaskell
+lexTextVar    isKnown = unknown2var (eitherUpper isKnown) . lexText
+
 
 eitherUpper isKnown w@(c:cs) = isKnown (toLower c : cs) || isKnown (toUpper c : cs)
 eitherUpper isKnown w = isKnown w

src/HelpFile

@@ -183,12 +183,12 @@ p,  parse: p String
       -fail      show strings whose parse fails prefixed by #FAIL
       -ambiguous show strings that have more than one parse prefixed by #AMBIGUOUS
   options for selecting parsing method:
-      (default)parse using an overgenerating CFG
+      -fcfg    parse using a fast variant of MCFG (default is no HOAS in grammar)
+      -old     parse using an overgenerating CFG (default if HOAS in grammar)
       -cfg     parse using a much less overgenerating CFG
       -mcfg    parse using an even less overgenerating MCFG
-      -fcfg    parse using a faster variant of MCFG
+      Note:    the first time parsing with -cfg, -mcfg, and -fcfg may take a long time
-      Note:    the first time parsing with -cfg, -mcfg, and -fcfg might take a long time
+  options that only work for the -old default parsing method:
-  options that only work for the default parsing method:
       -n       non-strict: tolerates morphological errors
       -ign     ignore unknown words when parsing
       -raw     return context-free terms in raw form
@@ -565,6 +565,7 @@ q, quit: q
     -lexer=chars         each character is a token
     -lexer=code          use Haskell's lex
     -lexer=codevars      like code, but treat unknown words as variables, ?? as meta 
+    -lexer=textvars      like text, but treat unknown words as variables, ?? as meta 
     -lexer=text          with conventions on punctuation and capital letters
     -lexer=codelit       like code, but treat unknown words as string literals
     -lexer=textlit       like text, but treat unknown words as string literals