_why's Markaby

You know that WebPage code I’ve been playing with lately? Tim Fletcher e-mailed me a revamped version, a plugin for Rails. We’ve gone back and forth on this and found a very satisfying resting point, which I’m calling Markaby. Markup as Ruby. To install in your Rails app: script/plugin install http://code.whytheluckystiff.net/svn/markaby/trunk To use it, add templates with a .mab extension. Examples For example, an app/views/layout/application.mab could look like:

     html do
       head do
         title action_name
         stylesheet_link_tag 'scaffold'
       end

       body do
         p flash[:notice], :style => "color: green" 
         self << @content_for_layout
       end
     end
    

As you can see all the normal helpers and variables are present. There is one caveat: in default Markaby, helper methods are automatically output when called. So, in the above, the stylesheet_link_tag gets output. (To turn that off, use @output_helpers = false.) A scaffolding page could look like this (app/views/products/list.mab):

     h1 'Listing products'

     table.editor.classic do 
       tr do
         for column in Product.content_columns
           th column.human_name
         end
       end 

       for product in @products
         tr do
           for column in Product.content_columns
             td product.send(column.name)
           end
           td { link_to 'Show', :action => 'show', :id => product }
           td { link_to 'Edit', :action => 'edit', :id => product }
           td { link_to 'Destroy', { :action => 'destroy', :id => product }, :confirm => 'Are you sure?' }
         end
       end
     end

     link_to 'Previous page', { :page => @product_pages.current.previous } if @product_pages.current.previous
     link_to 'Next page', { :page => @product_pages.current.next } if @product_pages.current.next

     br

     link_to 'New product', :action => 'new'
    

As you can see classes can be assigned just like in previous experiments. The table.editor.classic gets output as <table class="editor classic">. One really wonderfully trippy thing about Markaby is that you can use capture to treat elements as strings, if you like. This satisfies one of Dgtized’s feature requests from a few days ago.

     div.menu do
       %w[5.gets bits inspect cult -h].map do |m|
         capture { link_to m, "/#{m}" }
       end.join(" | ")
     end
    

So, in the above example, the output of link_to is captured for each element of the array and then patched together with pipes between. But how does it get output to div.menu? The rule is: each element with a block opens a new buffer. You can fill up that buffer by printing elements to it. Or by returning a string from the block. Markup Shortcuts Really, there’s not much more to this at present. For example, RedCloth support isn’t built in, nor is the auto-header and auto-body stuff from WebPage. Just a few shortcuts:

1. img tags will default to :alt => '', :border => 0.
2. head automatically includes tag!(:meta, 'http-equiv' => 'Content-Type', 'content' => 'text/html; charset=utf-8').
3. html defaults to an xml instruction, the XHTML 1.0 Transitional doctype and :xmlns => "http://www.w3.org/1999/xhtml", "xml:lang" => "en", :lang => "en" on the html element.
4. xhtml_transitional is an alias for html.
5. xhtml_strict does the same, but with the proper XHTML 1.0 Strict doctype and so on.

If you don’t like any of this, override or undef the methods. So far so good?