my @failures = grep { !/$regex/ } @array;
  if ( @failures ) {
     warn "Validation failure.  Bad names: @failures\n";
  }

##</code><code>##

  my %valid_names;
  @valid_names{ qw/ A B C D E / } = (); # define the set of valid names.

  my @failures = grep { ! exists $valid_names{$_} } @array;
  # and so forth.