Recently, I started looking for something new to work on. I decided to start playing around with Ruby and in the process, found the radius library. It’s a pure Ruby implementation of the same sort of XML-based templates used by Movable Type and TextPattern. I got to playing around with it, just to see what it can do. Here’s the test code: require ‘radius’ class User def initialize(name, login, password) @name = name @login = login @password = password end def name() @name end def login() @login end def password() @password end end context = Radius::Context.new context.define_tag “users” do |tag| content = ” [ User.new('Mike', 'MikeRT', 'testing1234'), User.new('John', 'JSmith', 'testing5678'), User.new('Jane', 'DoeJ', 'testing!@#$') ].each do |user| tag.locals.user = user content << tag.expand end content end context.define_tag “user”, :for => User, :expose => [ :name, :login, :password ] do |tag| content = ” tag.locals.user = User.new(‘Mike’, ‘MikeRT’, ‘testing1234′) if tag.locals.user.nil? content << tag.expand content end parser = Radius::Parser.new(context, :tag_prefix => ‘radius’) template = <<-TEMPLATE

Properties

TEMPLATE puts parser.parse(template) The part that I found the most impressive about it was how easy it was to expose an object with a few lines of code. That was done with this line: context.define_tag “user”, :for => User, :expose => [ :name, :login, :password ] do |tag| Very impressive. In a single line of code you tell the context to define a block tag called user for the class User and to expose User’s methods name, login and password as new tags. It’s actually a step beyond the capabilities that Movable Type and Melody have where to do the equivalent, you’d have to do something like this: sub hdlr_user_name { my ($ctx, $args, $cond) = @; my $user = $ctx->stash(‘user’) || return $ctx->error(‘No user!’); return $user->name; } (Though to be fair, it is incredibly easy to add new tags to Movable Type and Melody since the whole tag registration process involves a little YAML and a little bit of Perl).