I'm converting an existing CGI style app from Apache/CGI to Starman/PSGI, and am running into trouble. The specific error I'm getting is: 
Body should be an array ref or filehandle: <html>...

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And my problem is that the ensuing stacktrace doesn't give me the problem starting point within my code. Does anyone have a pointer to a good debugger for plack? I've seen references for one of the REST (browser based) plugins. I'm just curious what people think is a good solution for apps that don't require a ton of setup. Thanks for pointing out an interesting feature of PLACK while requesting an example of my code. Below, please find the snippet from my code which isn't working: 
#!/usr/bin/perl
use strict;
use Plack::Request;
use Plack::Builder;
use Plack::App::File;
use HTML::Template;

my $app = sub{
    my $env = shift;
    my $html = get_html();
    my $request = Plack::Request->new($env);

    if($request->param('file')){
        $html = thankyou();
    }

    return ['200', ['Content-Type'=>'text/html'],[$html]];
};

sub get_html{
    # open the html template
    my $template = HTML::Template->new(filename => 'scriptup.html');
    return $template->output();
}

sub thankyou{
    return <<HTML;
    <html><body>Thanks!</body></html>
HTML
}

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In reply to New Plack App (with HTML::Template & file upload) help by Evan Carew

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