use YAPE::Regex::Explain; my $name = 'asdf'; die YAPE::Regex::Explain->new(qr/.*${name}-*/)->explain; __END__ The regular expression: (?-imsx:.*asdf-*) matches as follows: NODE EXPLANATION ---------------------------------------------------------------------- (?-imsx: group, but do not capture (case-sensitive) (with ^ and $ matching normally) (with . not matching \n) (matching whitespace and # normally): ---------------------------------------------------------------------- .* any character except \n (0 or more times (matching the most amount possible)) ---------------------------------------------------------------------- asdf 'asdf' ---------------------------------------------------------------------- -* '-' (0 or more times (matching the most amount possible)) ---------------------------------------------------------------------- ) end of grouping ----------------------------------------------------------------------