# assume all encode/decode works correctly
  my $regexp_raw = "....";
  my $regexp_utf8_decoded = decode($some_enc, $regex_raw);
  my $regexp_utf8_encoded = encode('utf8', $regexp_utf8_decoded);


  my $some_content = "...";
  my $some_content_decoded = decode($some_enc, $some_content);
  my $some_content_encoded = encode('utf8', $some_content_decoded);

  $some_content_decoded =~ /$regexp_utf8_decded/; # matches correctly
  $some_content_decoded =~ /$regexp_utf8_encoded/; # matches correctly
  $some_content_encoded =~ /$regexp_utf8_decoded/; # no
  $some_content_encoded =~ /$regexp_utf8_encoded/; # no