my %swap = (
   name_1 => $name_1,
   name_2 => $name_2,
   name_3 => $name_3,
   name_4 => $name_4,
   name_5 => $name_5, 
   name_6 => $name_6,
);
WHILE (<MYTEMPLATE>) {
  s{<\?--(name_\d+)-->}{
    defined($swap{$1}) ? $swap{$1} : ''
  }eg;
}