Here is a way to use a template to generate the html (as 1nickt suggested). I used Template::Tiny, since it is a lightweight templating system whose syntax is compatible with the more feature rich Template::Toolkit. If you have Template::Toolkit installed you should be able to replace use Template::Tiny; with use Template; 
#!/usr/bin/perl

use strict;
use warnings;
use diagnostics;

use Template::Tiny;

my $app = sub {
    my $html = get_html();
    return [ 200, ['Content-Type' => 'text/html'], [$html] ];
};


sub get_html{
    my @array;
    $array[0] = 'happy';
    $array[1] = 'sad';
    $array[2] = 'worrried';

    my $template = do { local $/; <DATA> };
    my $tt = Template::Tiny->new();
    my $html;
    $tt->process(\$template, { my_array => \@array }, \$html); 
    return $html;
} 

__DATA__
<html>
    <head></head>
        <body>
            <select>
            [% FOREACH item IN my_array %]<option value='[% item %]'>[
+% item %]</option>
            [% END %]</select>
        </body>
</html>

[download]

In reply to Re: How do I run a loop within a PSGI application by kevbot
in thread How do I run a loop within a PSGI application by tiny_monk

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