The advantage of your function is to work with Perl-5.6 too, since it check for group of bytes. But since that's no meaning to check the UTF-8 on Perl without support, since the user won't be able to generate and work with true UTF-8 data, I made that (please check if it's ok): 
sub _is_unicode {
  if ($] >= 5.8) {
    eval(q`
      if ( $data =~ /[\x{100}-\x{10FFFF}]/s) { return 1 ;}}
    `);
  }
  else {
    ## No Perl support for UTF-8! ;-/
    return undef ;
  }

  return undef ;
}

[download]
I made this based in table at section #Unicode_Encodings in this POD: http://search.cpan.org/author/JHI/perl-5.8.0/pod/perlunicode.pod

Note that when the user isn't in Perl 5.8 I don't want, actually can't, handle the UTF-8, since the implementation was there only to handle UTF-8 as a group of bytes, not as characters. Note that for Perl 5.7 (that isn't stable) I won't hanbdle UTF-8 too.

Now I have a big problem. All the computer that I have here are based on ASCII-extended (ISO-8859-1), and for us is just what we need. But is impossible to tell that you made Unicode support without really test it on UTF-8 platforms (EBCDIC), like a Japanese PC. So, any one have some idea, or a Japanese PC?

Graciliano M. P.
"The creativity is the expression of the liberty".

In reply to Re: Re: How to know if a string has UTF-8? by gmpassos
in thread How to know if a string has UTF-8? by gmpassos

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