Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!rbj
From: rbj@uunet.UU.NET (Root Boy Jim)
Newsgroups: comp.lang.perl
Subject: Re: Comparing numbers and regular expressions
Message-ID: <120866@uunet.UU.NET>
Date: 2 Feb 91 02:31:27 GMT
References: <5152@s3.ireq.hydro.qc.ca>
Organization: UUNET Communications Services, Falls Church, VA
Lines: 26

In<5152@s3.ireq.hydro.qc.ca>gamin@ireq-robot.hydro.qc.ca (Martin Boyer) writes:
>$uid_list = "13|1";
>$this_uid = 101;
>if ($this_uid =~ /^$uid_list$/o) {
>    print "Matches!\n";
>} else {
>    print "Doesn't match.\n";
>}
>
>This section prints Matches!, but that's not what I want; what I want
>is for the test to succeed only for values of 13 or 1.

You fell into an age old regular expression trap. You just compiled
the pattern "^13|1$", which matches 13 at BOL or 1 at EOL. It has
nothing to do with numbers, as substitution will show you.

You need to compile /^($uid_list)$/o, or put each list member
explicitly between ^ and $.

>Can anybody enlighten me?

No, but at least I can fix your perl problem for you.
-- 

	Root Boy Jim Cottrell <rbj@uunet.uu.net>
	Close the gap of the dark year in between