This seems not a problem of Template. I also want advice for this.

“Séan”'s é may be 00E9 of unicode table http://www.utf8-chartable.de/unicode-utf8-table.pl. I thought decode it to perl internal utf8 and pass them to Template encoding it utf8 will work. But it is not work. Without Template, there is strange behavior.

#!/usr/bin/perl

use strict;
use warnings;

use Encode qw(is_utf8 encode decode);
use Template;

my(@raw, @decoded_internal_utf8,@encoded_raw_utf8,@encoded_internal_ut
+f8);

my @chars=hex('00C0') .. hex('00F0'); #target characters
#my @chars=hex('3041') .. hex('3096'); #hiragana

foreach my $code ( @chars ){
    my($raw, $chr);
    $raw =chr($code);
    if ( is_utf8($raw) ){
        $chr=$raw;
    } else {
        $chr=decode('utf8',$raw);
    }

    push @raw, $raw;
    push @decoded_internal_utf8, $chr;
    push @encoded_raw_utf8 , encode('utf8', $raw);
    push @encoded_internal_utf8, encode('utf8', $chr);
}
print "======================\n";
print "perl=$^X : version=$]\n";
print "1.###raw\n";
print "#$_#\n" for @raw;

print "2.###decoded_intenal_utf8\n";
#print "#$_#\n" for @decoded_internal_utf8;

print "3.###encoded_raw_utf8\n";
print "#$_#\n" for @encoded_raw_utf8;

print "4.###encoded_internal_utf8\n";
print "#$_#\n" for @encoded_internal_utf8;
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I saw similar problem at Why Doesn't Text::CSV_XS Print Valid UTF-8 Text When Used With the open Pragma?. At that time, I didn't understand well and thought newer version would have no problem... Is this the same trouble? I tried with 5.012002 and 5.014002. They print exact same output except version number.

I'm confused by your code, what is it supposed to demonstrate? perlunitut: Unicode in Perl warns against using is_utf8, so I wouldn't use it

Consider

$ perl -le " print chr hex q/C0/ " | od -tx1
0000000 c0 0d 0a
0000003
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when viewed as Windows-1252 it is À

And this

$ perl -le " binmode STDOUT , q/:utf8/; print chr hex q/C0/ " | od -tx
+1
0000000 c3 80 0d 0a
0000004
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when viewed as Windows-1252 it is À but viewed as UTF-8 it is 
And this

$ perl -MEncode -le " print decode(q/utf8/, chr hex q/C0/ )" | od -tx1
Wide character in print at -e line 1.
0000000 ef bf bd 0d 0a
0000005
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when viewed as Windows-1252 it is � but viewed as UTF-8 it is �

If you search for ef bf bd you'll see lots of questions about this erroneous conversion

So if you want to treat chr 192 (  perl -le " print  hex q/C0/ " ) as unicode you have to encode it, because characters 0 to 255 are also valid Latin-1, they are not utf8

$ perl -le " print chr hex q/C0/ " |od -tx1
0000000 c0 0d 0a
0000003

$ perl -le " print chr 255 " |od -tx1
0000000 ff 0d 0a
0000003

$ perl -le " print chr 256 " |od -tx1
Wide character in print at -e line 1.
0000000 c4 80 0d 0a
0000004
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Or, if you want chr 192 to return unicode, use encoding pragma ( utf8 pragma doesn't affect chr )

$ perl -le " use encoding q/utf8/; print chr 192 " |od -tx1
0000000 c3 80 0a
0000003
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