Importing Method Groups (Webmaster in a Nutshell, 3rd Edition)

14.2. Importing Method Groups

The syntax for calling CGI methods can be unwieldy. However, you can import individual methods and then call the methods without explicit object calls. The "birthday" example shown earlier could be written even more simply as follows:

#!/usr/bin/perl

use CGI param,header,p;

$bday = param("birthday");
print header( );
print p("Your birthday is $bday.");

By importing the param, header, and p methods into your namespace, you no longer have to use the new constructor (since it is called automatically now), and you don't need to specify a CGI object with every method call.

CGI.pm also lets you import groups of methods, which can make your programs much simpler and more elegant. For example, to import all form-creation methods and all CGI-handling methods:

use CGI qw/:form :cgi/;

The method groups supported by CGI.pm are:

:cgi: All CGI-handling methods
:cgi-lib: All methods supplied for backwards compatibility with cgi-lib
:form: All form-generation methods
:html: All HTML methods
:html2: All HTML 2.0 methods
:html3: All HTML 3.0 methods
:html4: All HTML 4.0 methods
:netscape: All methods generating Netscape extensions
:ssl: All SSL methods
:standard: All HTML, form-generation, and CGI methods
:all: All available methods

You can also define new methods for HTML tag generation by simply listing them on the import line and letting CGI.pm make some educated guesses. For example:

use CGI shortcuts,smell;

print smell {type=>'garlic',
           intensity=>'strong'}, "Scratch here!";

This causes the following tag to be generated:

<SMELL TYPE="garlic" INTENSITY="strong">Scratch here!</SMELL>