最近做公司的项目，接触到了haml。真是耳目一新，语法太简洁了，页面代码量也少了，也不会出现标签不匹配的问题了，用起来非常爽！下面我来介绍如何在rails中使用haml
1. 创建测试工程：
$rails test_haml
$cd test_haml
2. 生成post模型：
$script/generate scaffold post title:string content:text
$rake db:migrate
3. 安装haml插件：
$script/plugin install git://github.com/nex3/haml.git
4. 修改view文件的erb为haml：
# app/views/layouts/posts.html.haml
!!! XML
!!!
%html{html_attrs('en')}
%head
%meta{'http-equiv' = 'content-type', :content = 'text/html;charset=UTF-8'}
%title= Posts: #{controller.action_name}
= javascript_include_tag :defaults
%body
%p{:style = color: green}= flash[:notice]
= yield
# app/views/posts/index.html.haml
%h1 Listing posts
%table
%tr
%th Title
%th Content
- @posts.each do |post|
%tr
%td=h post.title
%td=h post.content
%td= link_to 'Show', post
%td= link_to 'Edit', edit_post_path(post)
%td= link_to 'Destroy', post, :confirm = 'Are you sure?', :method = :delete
%br
= link_to 'New post', new_post_path
# app/views/posts/show.html.haml
%p
%b Title:
=h @post.title
%p
%b Content:
=h @post.content
= link_to 'Edit', edit_post_path(@post)
= |
= link_to 'Back', posts_path
# app/views/posts/new.html.haml
%h1 New post
- form_for(@post) do |f|
= f.error_messages
%p
= f.label :title
%br
= f.text_field :title
%p
= f.label :content
%br
= f.text_area :content
%p
= f.submit 'Create'
= link_to 'Back', posts_path
# app/views/posts/edit.html.haml
%h1 Editing post
- form_for(@post) do |f|
= f.error_messages
%p
= f.label :title
%br
= f.text_field :title
%p
= f.label :content
%br
= f.text_area :content
%p
= f.submit 'Update'
= link_to 'Show', @post
= |
= link_to 'Back', posts_path
5. 用sass代替css：
$ mkdir public/stylesheets/sass
$ css2sass public/stylesheets/scaffold.css > public/stylesheets/sass/scaffold.sass
下面你就可以享受haml为你带来的高效啦！当然你完全可以找到生成haml的generator，这里只是展示一下haml的简洁而已
