haml_in_effigy.rb

require 'rubygems'
require 'haml'
require 'effigy'
require 'effigy/core_ext/hash'

template = Haml::Engine.new(%{%html
  %head
    %title
  %body
    %h1
    %p.body
    .comment
      %h2
      %p
      %a View more
    %p{:id => "no-comments"} There aren't any comments for this post.
}).render

class PostView < Effigy::View
  attr_reader :post

  def initialize(post)
    @post = post
  end

  def transform
    text('h1', post.title)
    text('title', "#{post.title} - Site title")
    text('p.body', post.body)
    replace_each('.comment', post.comments) do |comment|
      text('h2', comment.title)
      text('p', comment.summary)
      attr('a', :href => url_for(comment))
    end
    remove('#no-comments') if post.comments.empty?
  end
  
  def url_for(comment)
    "/comments/#{comment.id}"
  end
  
end

Comment = Struct.new(:id, :title, :summary)
Post = Struct.new(:title, :body, :comments)

post = Post.new("Post title", "Post body", [])
post.comments << Comment.new(1, "First comment title", "First comment body")
post.comments << Comment.new(2, "Second comment title", "Second comment body")

view = PostView.new(post)
puts view.render(template)