Good monks, Once again I apologize for disturbing your heavenly peace ;-). I come to you with this question:

I wrote a cgi script to emulate SSI behaviour and it works fine for the latest versions of perl (5.6.1+). Now I'm having to port this script to run under perl 5.005_02. I know this one is outrageously old, but one particular server I have to run the cgi on doesn't run any better ;(.

The cgi in question is http://www.e-vris.com/ssi_cgi.txt (http://www.e-vris.com/ssi.tar.gz)

While porting, I ran into this one problem where a regular expression would return 1 (true) on an empty string, whereas in perl 5.6.1 it returns 0, as is expected. For example, 

. . .
 
my $query = undef;
if ($query =~ /^(([\w\d\-\_]+)[:,]|)(.*)$/) {
    # we get here!
    print "$`|$1|$2|$3|$4|$'|$query|";

} else {
    exit;
}

. . .

[download]
Any idea why the regexp operation evaluates to 1? There should be absolutely no match... Afterall, the query variable is undefined.

Your help is much appreciated ;-) Update: Gush... this was an obviously stupid question. Sorry for the trouble. I'll get on with porting (occassional brain farts are not pleasant, especially when exposed) ;-p



_____________________
"I'm always right and I can prove it, because to the best of my knowledge, I've never been wrong."

In reply to regexp issue: Porting script from 5.6.1 to 5.005_02 by vladb

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