my @words = qw/one One/;

my $pattern = 'one';

foreach (@words) {
   # case-sensitive so 'one' is matched but not 'One'
   # but I would to to be able to enable case-sensitivity
   # in some cases to match both 'one' and 'One'
   if (/$pattern/) {
      print "Matched: pattern was $pattern and token was $_\n";
   }
   else {
      print "Unmatched: pattern was $pattern and token was $_\n";
   }
}