use strict;
use warnings;
use feature qw( say );

use Encode qw( );

my $orig = "\xE8\xAB\x86\x0A";

utf8::encode( my $enc_once = $orig );
utf8::encode( my $enc_twice = $enc_once );
say('length = ', length($orig));


{
   say("Using utf8::decode");
   utf8::decode( my $dec_once = $enc_twice );
   utf8::decode( my $dec_twice = $dec_once );
   say('length = ', length($dec_twice));
   say($orig eq $dec_twice ? 'ok' : 'not ok');
}

{
   say("Using Encode::decode");
   my $dec_once = Encode::decode('UTF-8', $enc_twice);
   my $dec_twice = Encode::decode('UTF-8', $dec_once);
   say('length = ', length($dec_twice));
   say($orig eq $dec_twice ? 'ok' : 'not ok');
}