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

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Trailing context is getting confused with trailing optional patterns
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     To: Adoram Rogel <adoram@hybridge.com>
     Subject: Re: Flex 2.5.4 BOF ???
     In-reply-to: Your message of Tue, 26 Nov 1996 16:10:41 PST.
     Date: Wed, 27 Nov 1996 10:56:25 PST
     From: Vern Paxson <vern>
     
     >     Organization(s)?/[a-z]
     >
     > This matched "Organizations" (looking in debug mode, the trailing s
     > was matched with trailing context instead of the optional (s) in the
     > end of the word.
     
     That should only happen with lex.  Flex can properly match this pattern.
     (That might be what you're saying, I'm just not sure.)
     
     > Is there a way to avoid this dangerous trailing context problem ?
     
     Unfortunately, there's no easy way.  On the other hand, I don't see why
     it should be a problem.  Lex's matching is clearly wrong, and I'd hope
     that usually the intent remains the same as expressed with the pattern,
     so flex's matching will be correct.
     
     		Vern