[project @ 2000-12-15 15:58:51 by simonmar]

Add a special case in doDiscard for the sequence '"'.  The
bootstrapped compiler can now build ghc/lib/std.

diff --git a/ghc/compiler/parser/Lex.lhs b/ghc/compiler/parser/Lex.lhs
index 2febf52..def163d 100644 (file)
--- a/ghc/compiler/parser/Lex.lhs
+++ b/ghc/compiler/parser/Lex.lhs
@@ -589,7 +589,7 @@ lexToken cont glaexts buf =
                    '#'# -> case lookAhead# buf 3# of
                                '#'# -> 
                                   let (lexeme, buf') 
-                                         = doDiscard False (stepOnBy# (stepOverLexeme buf) 4#) in
+                                         = doDiscard 0# (stepOnBy# (stepOverLexeme buf) 4#) in
                                             cont (ITpragma lexeme) buf'
                                _ -> lex_prag cont (setCurrentPos# buf 3#)
                    _    -> cont ITocurly (incLexeme buf) 
@@ -1076,13 +1076,13 @@ lex_ubx_tuple cont mod buf back_off =
 \end{code}
 
 -----------------------------------------------------------------------------
-doDiscard rips along really fast, looking for a '#-}', 
+doDiscard rips along really fast, looking for a '##-}', 
 indicating the end of the pragma we're skipping
 
 \begin{code}
 doDiscard inStr buf =
  case currentChar# buf of
-   '#'# | not inStr ->
+   '#'# | inStr ==# 0# ->
        case lookAhead# buf 1# of { '#'# -> 
        case lookAhead# buf 2# of { '-'# ->
        case lookAhead# buf 3# of { '}'# -> 
@@ -1090,24 +1090,32 @@ doDiscard inStr buf =
        _    -> doDiscard inStr (incLexeme buf) };
         _    -> doDiscard inStr (incLexeme buf) };
         _    -> doDiscard inStr (incLexeme buf) }
+
    '"'# ->
        let
         odd_slashes buf flg i# =
           case lookAhead# buf i# of
           '\\'# -> odd_slashes buf (not flg) (i# -# 1#)
           _     -> flg
+
+       not_inStr = if inStr ==# 0# then 1# else 0#
        in
        case lookAhead# buf (negateInt# 1#) of --backwards, actually
         '\\'# -> -- escaping something..
-          if odd_slashes buf True (negateInt# 2#) then
-              -- odd number of slashes, " is escaped.
-             doDiscard inStr (incLexeme buf)
-          else
-              -- even number of slashes, \ is escaped.
-             doDiscard (not inStr) (incLexeme buf)
-         _ -> case inStr of -- forced to avoid build-up
-              True  -> doDiscard False (incLexeme buf)
-               False -> doDiscard True  (incLexeme buf)
+          if odd_slashes buf True (negateInt# 2#) 
+               then  -- odd number of slashes, " is escaped.
+                     doDiscard inStr (incLexeme buf)
+               else  -- even number of slashes, \ is escaped.
+                     doDiscard not_inStr (incLexeme buf)
+         _ -> doDiscard not_inStr (incLexeme buf)
+
+   '\''# | inStr ==# 0# ->
+       case lookAhead# buf 1# of { '"'# ->
+       case lookAhead# buf 2# of { '\''# ->
+          doDiscard inStr (setCurrentPos# buf 3#);
+       _ -> doDiscard inStr (incLexeme buf) };
+       _ -> doDiscard inStr (incLexeme buf) }
+
    _ -> doDiscard inStr (incLexeme buf)
 
 \end{code}