[project @ 2001-09-26 09:16:00 by simonmar]

[ghc-hetmet.git] / ghc / compiler / parser / Lex.lhs

diff --git a/ghc/compiler/parser/Lex.lhs b/ghc/compiler/parser/Lex.lhs
index b4c9bc4..2a193d8 100644 (file)
--- a/ghc/compiler/parser/Lex.lhs
+++ b/ghc/compiler/parser/Lex.lhs
@@ -498,25 +498,28 @@ line_prag cont buf s@PState{loc=loc} =
   }}}}
 
 nested_comment :: P a -> P a
-nested_comment cont buf = loop buf
+nested_comment cont buf orig_state@PState{loc=loc} = loop buf orig_state
  where
    loop buf = 
      case currentChar# buf of
-       '\NUL'# | bufferExhausted (stepOn buf) -> 
-               lexError "unterminated `{-'" buf -- -}
-       '-'# | lookAhead# buf 1# `eqChar#` '}'# ->
-               cont (stepOnBy# buf 2#)
+       '-'# | lookAhead# buf 1# `eqChar#` '}'# -> cont (stepOnBy# buf 2#)
 
        '{'# | lookAhead# buf 1# `eqChar#` '-'# ->
              nested_comment (nested_comment cont) (stepOnBy# buf 2#)
 
        '\n'# -> \ s@PState{loc=loc} ->
                 let buf' = stepOn buf in
-                nested_comment cont buf'
-                       s{loc = incSrcLine loc, bol = currentIndex# buf',
-                         atbol = 1#}
+                loop buf' s{loc = incSrcLine loc, 
+                            bol = currentIndex# buf',
+                            atbol = 1#}
+
+       -- pass the original state to lexError so that the error is
+       -- reported at the line it was originally on, not the line at
+       -- the end of the file.
+       '\NUL'# | bufferExhausted (stepOn buf) -> 
+               \_ -> lexError "unterminated `{-'" buf orig_state -- -}
 
-       _   -> nested_comment cont (stepOn buf)
+       _   -> loop (stepOn buf)
 
 -- When we are lexing the first token of a line, check whether we need to
 -- insert virtual semicolons or close braces due to layout.