(flex.info.gz) The ^ operator isn't working

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 The ^ operator isn't working
 ============================
 
 
      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
 

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(flex.info.gz) Why can't flex understand this variable trailing context pattern?

(flex.info.gz) FAQ

(flex.info.gz) Trailing context is getting confused with trailing optional patterns