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To: Thomas Hadig <hadig@toots.physik.rwth-aachen.de>
Subject: Re: Flex Bug ?
In-reply-to: Your message of Tue, 26 Nov 1996 14:35:01 PST.
Date: Tue, 26 Nov 1996 11:15:05 PST
From: Vern Paxson <vern>
> In my lexer code, i have the line :
> ^\*.* { }
>
> Thus all lines starting with an astrix (*) are comment lines.
> This does not work !
I can't get this problem to reproduce - it works fine for me. Note
though that if what you have is slightly different:
COMMENT ^\*.*
%%
{COMMENT} { }
then it won't work, because flex pushes back macro definitions enclosed
in ()'s, so the rule becomes
(^\*.*) { }
and now that the '^' operator is not at the immediate beginning of the
line, it's interpreted as just a regular character. You can avoid this
behavior by using the "-l" lex-compatibility flag, or "%option lex-compat".
Vern