my $field_index = $position{$field};
if ("text" eq $type{$field}) {
  if ("asc" eq $order{$field}) {
    push @sort_sub, sub ($$) {
      $_[0][0][$field_index] cmp $_[1][0][$field_index];
    };
  }
  else {
    push @sort_sub, sub ($$) {
      $_[1][0][$field_index] cmp $_[0][0][$field_index];
    };
  }
}
else {
  if ("asc" eq $order{$field}) {
    push @sort_sub, sub ($$) {
      $_[0][0][$field_index] <=> $_[1][0][$field_index];
    };
  }
  else {
    push @sort_sub, sub ($$) {
      $_[1][0][$field_index] <=> $_[0][0][$field_index];
    };
  }
}