comment on

Nice progress! You don't even need the Encode module :)

This is a pretty straightforward way to deal with Unicode and UTF-8.

The remaining mentions of UTF-8 in your code have all their justification:

use utf8; tells Perl that your source code comes with UTF-8 encoded literals.
binmode STDOUT, ':utf8'; makes Perl spit out the strings in @html properly UTF-8 encoded. You can encode any Unicode character in UTF-8, so no problems here.
Content-Type: text/html; charset=utf-8 tells the browser that it has to handle the byte stream as UTF-8 and decode the characters accordingly.

There are two caveats:

Obviously, You need to save your source code UTF-8 encoded.

You must check whether the JSON data might, in some circumstances, contain characters which have a special meaning in HTML, in particular < and &. This has nothing to do with Unicode, though. I'm adding the relevant stuff to your sub display_html:

sub display_html {
    use HTML::Entities;
    my $html_encoded = encode_entities(shift, '<>&"');
    my @html = (
        '<!DOCTYPE html>',
        '<html>',
        '<head>',
        '<meta charset="UTF-8">',
        '<title>Мой тест</title>',
        '</head>',
        '<body>',
        $html_encoded // 'Статус — ОК', # soft OR: 0 and empty string accepted
        '</body>',
        '</html>'
    );
    
    # to avoid "wide character" warnings:
    binmode STDOUT, ':utf8';
    
    print "Content-Type: text/html; charset=utf-8\n\n";
    
    print join("\n", @html);
}

In reply to Re: Proper Unicode handling in Perl by haj
in thread Is there some universal Unicode+UTF8 switch? by VK

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