Great CPAN Modules

OO support in Perl 5 to provide a simpler way to write CGI scripts. CGI.pm also 

included many new features, particularly extensive support for HTML generation.

The most obvious reason CGI.pm is so popular is that it represents a complete 

solution to a difficult problem. Nearly every capability you could want in a CGI 

environment is present, from parameter parsing to file uploads to cookie handling 

to HTML form generation. All of these capabilities are documented clearly with 

full examples of nearly every possible usage.

Another highlight is the interface design. Lincoln Stein has embraced 

TMTOWTDI

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 to a degree that few have managed. For example, a critical task in 

CGI is parameter parsing and processing. CGI.pm provides five different ways to 

access the CGI parameters. Many of these are supplied to allow for backwards com 

patibility with older libraries and older versions of CGI.pm. Stein has always focused 

on keeping older scripts working even as he enhances CGI.pm with new features.

Furthermore, CGI.pm provides its functionality through both object oriented 

and functional interfaces. This is accomplished by starting each and every sub 

routine in CGI.pm as follows:

sub method_foo {

   my($self,@p) = self_or_default(@_);

The self_or_default() routine extracts $self from @_, or if $self is not found uses a 

globally defined CGI object instead. This means that users can pick either an 

object oriented style:

use CGI;

my $cgi = CGI >new;

print join "\n", $cgi >param();

or functional calling style:

use CGI qw(param);

print join "\n", param();

People writing quick scripts can benefit from the brevity of the functional inter 

face, whereas those developing more intensive CGI code can benefit from the 

extensibility of the OO interface.

6. Short for  There's more than one way to do it. 

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