Destroyed Using Liquid without Rails (textile)

Using-Liquid-without-Rails.textile

@@ -1,115 +0,0 @@
-Want to use Liquid along with some plain old Ruby code?
-First, of course, you need to tell Ruby about the Liquid library.
-Assuming that you're in the @liquid@ directory, as cloned from GitHub,
-just @require 'lib/liquid'@.
-
-The big secret, however, is creating a @to_liquid@ method for any classes you want Liquid to access.
-
-Let's say you have a Product class:
-
-<pre>
-class Product
-  attr_accessor :name, :price
-
-  def initialize(name,price)
-    @name  = name
-    @price = price
-  end
-end
-</pre>
-
-And you have a chunk of text that you want to Liquidize by inserting some details about your products:
-
-<pre>
-sentence = "I'm running to the store with {{ product.price }} dollars in my pocket "
-sentence += "to buy a {{ product.name }}."
-</pre>
-
-And you create a product and parse the sentence:
-
-<pre>
-my_purchase = Product.new('box of sausages', 20)
-puts Liquid::Template.parse(sentence).render('product' => my_purchase)
-</pre>
-
-You excitedly execute your code, expecting to see your beautiful new sentence, but instead you get:
-
-<pre>
-I'm running to the store with Liquid error:
-undefined method `to_liquid' for #<Product:0x1388c08 ...
-</pre>
-
-@to_liquid@ ???
-Where did that come from?
-Turns out you need to add a method to your class that returns your instance variables as part of a hash.
-(Liquid was built to be very paranoid about not letting people access something they're not supposed to,
-so you need to explicitly let Liquid know how to access everything in your object.)
-So, we update the @Product@ class description to include that method:
-
-<pre>
-class Product
-  attr_accessor :name, :price
-
-  def initialize(name, price)
-    @name  = name
-    @price = price
-  end
-
-  def to_liquid
-    { "name"  => self.name,
-      "price" => self.price }
-  end
-end
-</pre>
-
-Run that again and presto:
-
-<pre>
-I'm running to the store with 20 dollars in my pocket to buy a box of sausages.
-</pre>
-
-However, that's a bit verbose, so you may want to use @liquid_methods@, instead:
-
-<pre>
-class Product
-  attr_accessor  :name, :price
-  liquid_methods :name, :price
-
-  def initialize(name, price)
-    @name  = name
-    @price = price
-  end
-end
-</pre>
-
-(Thanks to "Tom's":http://github.com/mojombo "Jekyll":http://github.com/mojombo/jekyll/tree/master/lib/jekyll/post.rb#L122-128 code for helping me figuring this out.)
-
-h2. A bit more detail
-
-Every variable rendered by liquid must either:
-* implement a @to_liquid@ method; or
-* be a Proc. This is called with the @Liquid::Context@ as a parameter and must return an object which responds to @to_liquid@
-
-Liquid defines @to_liquid@ for the following standard classes: String,  Array, Hash, Numeric, Time, DateTime, Date, TrueClass, FalseClass, NilClass. For each of these, @to_liquid@ just returns the object itself. <em>(See: lib/liquid/extensions.rb)</em>
-
-If the value returned by @to_liquid@ is inserted into the output, it will be further converted with @to_s@ <em>(actually this is done implicitly by Array#join - see lib/liquid/template.rb)</em>
-
-When used in a chained expression like @foo.bar@ or @foo['bar']@, the result of @to_liquid@ on the left-hand subexpression must either:
-* respond to @has_key?@ and @[]@ (i.e. duck-type like a Hash); or
-* respond to @fetch@ and @[]@ with an Integer argument (i.e. duck-type like an Array); or 
-* respond to @size@ or @first@ or @last@
-
-In each case, the object returned after applying the right-hand subexpression must also respond to @to_liquid@ or be a Proc which returns an object that responds to @to_liquid@. In the latter case, it will only be called if the previous element in the chain also responds to @[]=@ - that is, if the value can be cached in the parent object.
-
-<em>(See: lib/liquid/context.rb)</em>
-
-<pre>
->> assigns = {"foo"=>{"bar"=>{"baz"=>lambda { |x| Time.now } }}}
-=> {"foo"=>{"bar"=>{"baz"=>#<Proc:0xb7cd9af8@(irb):11>}}}
->> t = Liquid::Template.parse("{{ foo.bar.baz }}")
-=> #<Liquid::Template:0xb7d2e738 ... >
->> t.render(assigns)
-=> "Fri Jun 05 11:23:56 +0100 2009"
->> assigns
-=> {"foo"=>{"bar"=>{"baz"=>Fri Jun 05 11:23:56 +0100 2009}}}
-</pre>