Article View: gnu.g++.lib.bug
Article #193Regex problem : matches empty strings
From: T.Day
Date: Sun, 26 Nov 1989 16:47
Date: Sun, 26 Nov 1989 16:47
24 lines
767 bytes
767 bytes
From: Tim Day <T.Day@uk.ac.ucl.cs>
On a Sun-3 (OS4) with ``gcc version 1.36.1 (based on GCC 1.36)''
comparing any empty string with a Regex always seems to evaluate to TRUE.
e.g....
#include <stream.h>
#include <String.h>
main()
{ if (String("").matches(Regex("xxx")))
cerr << "OOPS!\n";
else cerr << "OK\n";
if (String("yyy").matches(Regex("xxx")))
cerr << "OOPS\n";
else cerr << "OK\n";
exit(0);
}
Outputs:
OOPS!
OK
Technical Details
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arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!uunet!mcsun!ukc!kl-cs!nott-cs!ucl-cs!T.DayShow Full Headers
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!uunet!mcsun!ukc!kl-cs!nott-cs!ucl-cs!T.Day From: T.Day@ucl-cs.UUCP Newsgroups: gnu.g++.lib.bug Subject: Regex problem : matches empty strings Message-ID: <472@ucl-cs.UUCP> Date: 26 Nov 89 16:47:58 GMT Sender: T.Day@ucl-cs.UUCP Lines: 24