I am processing a form submission from a web page, and I am having trouble accepting '0' as a valid value in my regex.

The regex should accept all single digits in addition to '*' and '#'. This is the regex that I am using, 
Readonly my $REGEX => qr/^\s*([0-9]|\*|\#)\s*$/;

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Later on I test the message against the regex, and it works for all expected values, except for '0'. 
    if ( $message =~ $REGEX ) {
        do_something($1);
    }
    else {
        do_something_else();
    }

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I have tested this exact code as a command line perl script, and had no trouble with it at all. I have also put in all kinds of debug statements to see if anything funky is being attached to the form parameter, and i have stripped null, and all spaces just for good measure to no avail.

I have even gone so far as to hard code $message="0"; just to try and isolate the problem, and even that fails the condition.
I think that there must be something in my web app that is somehow changing the default behavior of the regex, but I have no idea what, and can't imagine what could be causing this?

I am running perl 5.8.8, Apache 2.2.6, and mod_perl in a linux environment. I am testing using firefox, and i admittedly have not tried it in another browser.

Any ideas? Thank you much.

In reply to Weird mod_perl Regex '0' behavior. by vansance

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