/
^                    # start
  (?:([\$\@\*\%])|<) # leading sigil or <
  (\w+)              # name
  (?(?{$1}) |> )     # if there was a leading sigil, match nothing;
                     # otherwise, match >
$                    # end
/x;

##</code><code>##

/
^                       # start
  ([\$\@\*\%<])         # sigil
  (\w+)                 # name
  (?(?{$1 eq '<'}) >| ) # if the sigil is a '<', match the end;
                        # otherwise match nothing 
$                       # end
/x;