Thanks, though adding use utf8 does not affect the result

Yes, it does.

... the host name needs to remain human-readable. The goal is to extract the host name from the URI and the host name happens to be Japanese as Unicode, ...

Corion already pointed you to Net::IDN::Encode as one possibility.

use warnings;
use strict;
use utf8;
use open qw/:std :encoding(UTF-8)/;
use URI;
use Net::IDN::Encode qw/domain_to_unicode/;

my $href="https://マリウス.com/";
my $uri = URI->new($href);
my $domain = domain_to_unicode($uri->host);
print $domain,"\n";  # prints "マリウス.com"

In reply to Re^3: CPAN's URI.pm versus Japanse as Unicode? by haukex
in thread CPAN's URI.pm versus Japanese as Unicode? by mldvx4

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