Haml/Slim 介绍

%strong => <strong></strong>
%strong.classname   => class="classname"
%strong#id          => id="id"
= print_information => insert ruby 
- 10.each do |i|    => running ruby
:markdown           => filter, use plugin process current text

<div id='content'>
  <div class='left column'>
    <h2>Welcome to our site!</h2>
    <p><%= print_information %></p>
  </div>
  <div class="right column">
    <%= render :partial => "sidebar" %>
  </div>
</div>

#content
  .left.column
    %h2 Welcome to our site!
    %p= print_information
  .right.column
    = render :partial => "sidebar"

<div class='item' id='item<%= item.id %>'>
  <%= item.body %>
</div>

.item{:id => "item#{item.id}"}= item.body

%div{:id => [@item.type, @item.number], :class => [@item.type, @item.urgency]}

# equal to 
%div{:id => "#{@item.type}_#{@item.number}", :class => "#{@item.type} #{@item.urgency}"}

%script(type="text/javascript"
        src="javascripts/script_#{2 + 7}")

<script src='javascripts/script_9' type='text/javascript'></script>

%p
  :markdown
    # Greetings

    Hello, *World*

<p>
  <h1>Greetings</h1>

  <p>Hello, <em>World</em></p>
</p>

-    => control code
=    => output code
==   => output without html escape
*    => convert hash to key value pairs
meta => directly as tag name 

.card*{'data-url'=>place_path(place), 'data-id'=>place.id} = place.name
.card *@hash_instance_variable = place.name

<div class="card" data-id="1234" data-url="/place/1234">Slim's house</div>

ruby:
  def a_unless_current
    @page_current ? {:tag => 'span'} : {:tag => 'a', :href => 'http://slim-lang.com/'}
  end
- @page_current = true
*a_unless_current Link
- @page_current = false
*a_unless_current Link

<span>Link</span><a href="http://slim-lang.com/">Link</a>

doctype html
html
  head
    title Slim Examples
    meta name="keywords" content="template language"
    meta name="author" content=author
    link rel="icon" type="image/png" href=file_path("favicon.png")
    javascript:
      alert('Slim supports embedded javascript!')

  body
    h1 Markup examples

    #content
      p This example shows you how a basic Slim file looks.

    == yield

    - if items.any?
      table#items
        - for item in items
          tr
            td.name = item.name
            td.price = item.price
    - else
      p No items found Please add some inventory.
        Thank you!

    div id="footer"
      == render 'footer'
      | Copyright © #{@year} #{@author}

# Linux + Ruby 1.9.2, 1000 iterations

                      user     system      total        real
(1) erb           0.680000   0.000000   0.680000 (  0.810375)
(1) erubis        0.510000   0.000000   0.510000 (  0.547548)
(1) fast erubis   0.530000   0.000000   0.530000 (  0.583134)
(1) slim          4.330000   0.020000   4.350000 (  4.495633)
(1) haml          4.680000   0.020000   4.700000 (  4.747019)
(1) haml ugly     4.530000   0.020000   4.550000 (  4.592425)

(2) erb           0.240000   0.000000   0.240000 (  0.235896)
(2) erubis        0.180000   0.000000   0.180000 (  0.185349)
(2) fast erubis   0.150000   0.000000   0.150000 (  0.154970)
(2) slim          0.050000   0.000000   0.050000 (  0.046685)
(2) haml          0.490000   0.000000   0.490000 (  0.497864)
(2) haml ugly     0.420000   0.000000   0.420000 (  0.428596)

(3) erb           0.030000   0.000000   0.030000 (  0.033979)
(3) erubis        0.030000   0.000000   0.030000 (  0.030705)
(3) fast erubis   0.040000   0.000000   0.040000 (  0.035229)
(3) slim          0.040000   0.000000   0.040000 (  0.036249)
(3) haml          0.160000   0.000000   0.160000 (  0.165024)
(3) haml ugly     0.150000   0.000000   0.150000 (  0.146130)

(4) erb           0.060000   0.000000   0.060000 (  0.059847)
(4) erubis        0.040000   0.000000   0.040000 (  0.040770)
(4) slim          0.040000   0.000000   0.040000 (  0.047389)
(4) haml          0.190000   0.000000   0.190000 (  0.188837)
(4) haml ugly     0.170000   0.000000   0.170000 (  0.175378)

1. Uncached benchmark. Template is parsed every time.
   Activate this benchmark with slow=1.

2. Cached benchmark. Template is parsed before the benchmark.
   The ruby code generated by the template engine might be evaluated every time.
   This benchmark uses the standard API of the template engine.

3. Compiled benchmark. Template is parsed before the benchmark and
   generated ruby code is compiled into a method.
   This is the fastest evaluation strategy because it benchmarks
   pure execution speed of the generated ruby code.

4. Compiled Tilt benchmark. Template is compiled with Tilt, which gives a more
   accurate result of the performance in production mode in frameworks like
   Sinatra, Ramaze and Camping. (Rails still uses its own template
   compilation.)