Does anybody please have an advice on how to get rid of the warnings Use of uninitialized value in pattern match (m//) without (ab)using the no warnings qw(uninitialized);?

I have a habit of untainting input data this way:

$user = $1 if $query->param('user') =~ /(\w{3,12})/;
$pass = $1 if $query->param('pass') =~ /(\w{8})/;
.....

unless ($user and $pass and ...) {
    print $query->start_form(), ...
} else {
    # do the real work with data
}

[download]

(for example see my full script for adding new users to AD and NIS) and thus I can't set $query->param('blah'); to an empty string '' before I try to match it.

Thank you for your wisdom

In reply to CGI.pm and Use of uninitialized value in pattern match by afarber

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