I think its because regular expressions have syntax of their own, and it seems you want to use eq 
die if 'stu\d' =~ /stu\d/;
die if 'stu\d' =~ 'stu\d';
die if 'stu\d' =~ /\Qstu\d\E/;
__END__
Died at - line 3.

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In reply to Re: Normal regexes stop working by Anonymous Monk
in thread Normal regexes stop working by yegg

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