Changeset 2940

Timestamp:

05/10/05 20:45:26 (4 years ago)

Author:

autrijus

svk:copy_cache_prev:

4498

Message:

* parse for //, rx//, m//, rule{}, and assorted other things.

Location:

src/Pugs

Files:

• Eval.hs (modified) (1 diff)
• Parser.hs (modified) (5 diffs)

src/Pugs/Eval.hs

@@ -541 +541 @@
             Just v  -> fromVal v
             Nothing -> fromAdverb hv ks
+    "//" -> reduce (Syn "rx" exps)
+    "match" -> reduce (Syn "rx" exps) -- XXX - this is wrong
     "subst" -> do
         let [exp, subst, adverbs] = exps

src/Pugs/Parser.hs

@@ -126 +126 @@
 mergeStmts (Sym scope name x) y = Sym scope name (mergeStmts x y)
 mergeStmts (Pad scope lex x) y = Pad scope lex (mergeStmts x y)
-mergeStmts x@(Pos pos (Syn "rx" _)) y =
+mergeStmts x@(Pos pos (Syn syn _)) y | (syn ==) `any` words "subst match //"  =
     mergeStmts (Pos pos (App (Var "&infix:~~") [Var "$_", x] [])) y
-mergeStmts x y@(Pos pos (Syn "rx" _)) =
-    mergeStmts x (Pos pos (App (Var "&infix:~~") [Var "$_", y] []))
-mergeStmts x@(Pos pos (Syn "subst" _)) y =
-    mergeStmts (Pos pos (App (Var "&infix:~~") [Var "$_", x] [])) y
-mergeStmts x y@(Pos pos (Syn "subst" _)) =
+mergeStmts x y@(Pos pos (Syn syn _)) | (syn ==) `any` words "subst match //"  =
     mergeStmts x (Pos pos (App (Var "&infix:~~") [Var "$_", y] []))
 mergeStmts x@(Pos pos (Syn "sub" [Val (VCode sub)])) y
@@ -1467 +1463 @@
 
 -- Regexps
+rxLiteralAny adverbs
+    | Syn "\\{}" [Syn "," pairs] <- adverbs
+    , not (null [ True | (App (Var "&infix:=>") [Val (VStr "P5"), _] []) <- pairs ])
+    = rxLiteral5
+    | otherwise
+    = rxLiteral6
+
 rxLiteral5 :: Char -- ^ Closing delimiter
              -> RuleParser Exp
@@ -1489 +1492 @@
     let endch = balancedDelim ch
     -- XXX - probe for adverbs to determine p5 vs p6
-    expr    <- rxLiteral5 endch
+    expr    <- rxLiteralAny adverbs endch
     ch      <- if ch == endch then return ch else do { whiteSpace ; anyChar }
     let endch = balancedDelim ch
@@ -1497 +1500 @@
 rxLiteral :: RuleParser Exp
 rxLiteral = try $ do
-    symbol "rx"
+    sym     <- symbol "rx" <|> do { symbol "m"; return "match" } <|> do
+        symbol "rule"
+        lookAhead (char '{')
+        return "rx"
     adverbs <- ruleAdverbHash
     ch      <- anyChar
     -- XXX - probe for adverbs to determine p5 vs p6
-    expr    <- rxLiteral5 $ balancedDelim ch
-    return $ Syn "rx" [expr, adverbs]
+    expr    <- rxLiteralAny adverbs $ balancedDelim ch
+    return $ Syn sym [expr, adverbs]
 
 rxLiteralBare :: RuleParser Exp
@@ -1508 +1514 @@
     ch      <- char '/'
     expr    <- rxLiteral6 $ balancedDelim ch
-    return $ Syn "rx" [expr, Val undef]
+    return $ Syn "//" [expr, Val undef]
 
 namedLiteral :: String -> Val -> RuleParser Exp