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From: merlyn@iwarp.intel.com (Randal Schwartz)
Newsgroups: comp.lang.c
Subject: the answer (I hope!) (was Re: regex for C comments)
Message-ID: <4644@omepd.UUCP>
Date: 13 Jul 89 15:50:55 GMT
References: <19365@paris.ics.uci.edu> <502@chem.ucsd.EDU>
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Reply-To: merlyn@iwarp.intel.com (Randal Schwartz)
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Organization: Stonehenge; netaccess via Intel, Hillsboro, Oregon, USA
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In-reply-to: tps@chem.ucsd.edu (Tom Stockfisch)

In article <502@chem.ucsd.EDU>, tps@chem (Tom Stockfisch) writes:
| So, who has the shortest single LEX expression that correctly
| matches C comments --
| ignoring string and character constants,
| and disallowing start conditions?
| 
| Mine is
| 
| 	"/*"\/*([^/]|{[^*/]\/+})*"*/"

What are these curly brace things?  They're not used in accordance
with V7 (the One True Unix :-) Lex.

OK, I'll toss my submission back in the ring, which I have tested (for
once... :-).

	"/*"("*"*[^*/]+|"/"+)*"*"+"/"

You could make it shorter by leaving off the two plus signs inside the
parens, but this is probably more efficient.

Ducking to avoid the onslaught of test cases,
-- 
/== Randal L. Schwartz, Stonehenge Consulting Services (503)777-0095 ====\
| on contract to Intel, Hillsboro, Oregon, USA                           |
| merlyn@iwarp.intel.com ...!uunet!iwarp.intel.com!merlyn	         |
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