Matching the newline here meant having to do some redundant work here,
(incrementing line number, resetting column number, and returning a
NEWLINE token), that could otherwise simply be left to the existing rule
which matches a newline.
Worse, when the comment rule matches the newline as well, the parser
can lookahead and see a token for something that should actually be skipped.
For example, in a case like this:
#if 0 // comment here
fail
#else
win
#endif
Both fail and win appear in the output, (not that the condition is being
evaluated incorrectly---merely that one token after the comment's newline
was being lexed/parse regardless of the condition).
This commit fixes the above test case, (which is also remarkably similar
to 087-if-comments which now passes).
%%
/* Single-line comments */
-"//"[^\n]*\n {
- yylineno++;
- yycolumn = 0;
- return NEWLINE;
+"//"[^\n]* {
}
/* Multi-line comments */