Mason::Manual::Intro - Getting started with Mason
A few quick examples to get your feet wet with Mason. See Mason::Manual::Setup for how to use Mason to generate web sites.
After installing Mason,
you should have a
mason command in your installation path (e.g.
% mason Hello! The local time is <% scalar(localtime) %>. ^D
(where '^D' means ctrl-D or EOF). You should see something like
Hello! The local time is Wed Mar 2 17:11:54 2011.
mason command reads in a Mason component (template), runs it, and prints the result to standard output. Notice that the tag
<% scalar(localtime) %>
was replaced with the value of its expression. This is called a substitution tag and is a central piece of Mason syntax.
The command line is good for trying quick things, but eventually you're going to want to put your Mason components in files.
In a test directory, create a directory
comps and create a file
email.mc with the following:
<%class> has 'amount'; has 'name'; </%class> Dear <% $.name %>, We are pleased to inform you that you have won $<% sprintf("%.2f", $.amount) %>! Sincerely, The Lottery Commission <%init> die "amount must be a positive value!" unless $.amount > 0; </%init>
In addition to the substitution tag we've seen before, we declare two attributes,
name, to be passed into the component; and we declare a piece of initialization code to validate the amount.
In the same test directory, create a script
test.pl with the following:
1 #!/usr/local/bin/perl 2 use Mason; 3 my $interp = Mason->new(comp_root => 'comps', data_dir => 'data'); 4 print $interp->run('/email', name => 'Joe', amount => '1500')->output;
Line 3 creates a Mason interpreter, the main Mason object. It specifies two parameters: a component root, indicating the directory hierarchy where your components will live; and a data directory, which Mason will use for internal purposes such as class generation and caching.
Line 4 runs the template - notice that the
.mc extension is added automatically - passing values for the
test.pl, and you should see
Dear Joe, We are pleased to inform you that you have won $1500.00! Sincerely, The Lottery Commission
Jonathan Swartz <firstname.lastname@example.org>
This software is copyright (c) 2012 by Jonathan Swartz.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.