in reply to How to Debug the CGI Codes

There are all sorts of methods you can employ for debugging CGI code - here are a couple that I often use: 
use CGI::Carp qw/fatalsToBrowser/;

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This will throw any errors or warnings to your browser. (Never leave this enabled in production code). 

use Data::Dumper::Simple;
print q(<pre>);
print Dumper(%foo);

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Useful for examining the contents of any data structure. 
my @params = param();
print q(<pre>);
for (@params) {
    print "$_ :: $params[$_]\n";
}

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Useful to find out which CGI parameters were passed and what their values are.

Hope this helps,
Darren :)

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Re^2: How to Debug the CGI Codes
by strat (Canon) on Jul 10, 2006 at 08:13 UTC

    For development, I even use:

    use CGI::Carp qw/fatalsToBrowser warningsToBrowser/;

    because it also handles warnings

    Update: is wrong, see the posting from reneeb below

    Best regards,
    perl -e "s>>*F>e=>y)\*martinF)stronat)=>print,print v8.8.8.32.11.32"

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      To handle warnings, you have to call the warningsToBrowser subroutine with a true argument. See documentation of CGI::Carp.
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      Just a note:
      warningsToBrowser(1) must be explicitly called after printing the page header, and will output all warnings as HTML comments. It's its difference from fatalsToBrowser, which catches all fatal errors (even compile-time!) without any additional actions. The CGI::Carp documentation contains additional info.

      UPD: i haven't seen the previous reply while writing this :)

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