See quotemeta, Regex::PreSuf, and read How do I post a question effectively? 
my $line = 'fee fi fo fum';
my $pat = qr/i smell the blood/;
unless( grep /$pat/, $line ){
    print "of an englishman\n";
}
__END__

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Prints "of an englishman", because $line doesn't match $pat

That condition is more commonly written as one of these 

unless( $line =~ /$pat/ ) { ...
if( not $line =~ /$pat/ ) { ...
if( $line !~ /$pat/ ) { ...

[download]

In reply to Re: unless condition not working by Anonymous Monk
in thread unless condition not working by perlavi

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