Would you like to put parenthesis around the text that you match that you'd like to keep? $1 will contain the value contained in the first set of parenthesis in the match. $2 will contain the value contained in the second set of parenthesis in the match. And so on. e.g.

  if ( $lastname =~ m/^([\s\w.'-]+)$/ ...
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It follows that if there are no parenthesis then $1 will be empty.