Update initialization guide [ci skip]

* update rails versions
* remove outdated code snippets
* few more corrections

1 files changed, 32 insertions, 64 deletions

diff --git a/guides/source/initialization.textile b/guides/source/initialization.textile
index 913ff24290..48d4373afe 100644
--- a/guides/source/initialization.textile
+++ b/guides/source/initialization.textile
@@ -57,7 +57,7 @@ else
 end
 </ruby>
 
-The +rbconfig+ file from the Ruby standard library provides us with the +RbConfig+ class which contains detailed information about the Ruby environment, including how Ruby was compiled. We can see thisin use in +railties/lib/rails/script_rails_loader+.
+The +rbconfig+ file from the Ruby standard library provides us with the +RbConfig+ class which contains detailed information about the Ruby environment, including how Ruby was compiled. We can see this in use in +railties/lib/rails/script_rails_loader+.
 
 <ruby>
 require 'pathname'
@@ -157,11 +157,11 @@ The gems that a Rails 4 application depends on are as follows:
 TODO: change these when the Rails 4 release is near.
 
 * abstract (1.0.0)
-* actionmailer (3.1.0.beta)
-* actionpack (3.1.0.beta)
-* activemodel (3.1.0.beta)
-* activerecord (3.1.0.beta)
-* activesupport (3.1.0.beta)
+* actionmailer (4.0.0.beta)
+* actionpack (4.0.0.beta)
+* activemodel (4.0.0.beta)
+* activerecord (4.0.0.beta)
+* activesupport (4.0.0.beta)
 * arel (2.0.7)
 * builder (3.0.0)
 * bundler (1.0.6)
@@ -174,8 +174,8 @@ TODO: change these when the Rails 4 release is near.
 * rack-cache (0.5.3)
 * rack-mount (0.6.13)
 * rack-test (0.5.6)
-* rails (3.1.0.beta)
-* railties (3.1.0.beta)
+* rails (4.0.0.beta)
+* railties (4.0.0.beta)
 * rake (0.8.7)
 * sqlite3-ruby (1.3.2)
 * thor (0.14.6)
@@ -191,6 +191,7 @@ ARGV << '--help' if ARGV.empty?
 
 aliases = {
   "g"  => "generate",
+  "d"  => "destroy",
   "c"  => "console",
   "s"  => "server",
   "db" => "dbconsole",
@@ -579,28 +580,6 @@ this time to the +Array+ and +Hash+ classes. This file defines an
 +extract_options!+ method which Rails uses to extract options from
 parameters.
 
-<ruby>
-class Array
-  # Extracts options from a set of arguments. Removes and returns the
-  # last
-  # element in the array if it's a hash, otherwise returns a blank hash.
-  #
-  #   def options(*args)
-  #     args.extract_options!
-  #   end
-  #
-  #   options(1, 2)           # => {}
-  #   options(1, 2, :a => :b) # => {:a=>:b}
-  def extract_options!
-    if last.is_a?(Hash) && last.extractable_options?
-      pop
-    else
-      {}
-    end
-  end
-end
-</ruby>
-
 h4. +railties/lib/rails/application.rb+
 
 The next file required by +railties/lib/rails.rb+ is +application.rb+.
@@ -612,8 +591,7 @@ Before the +Rails::Application+ class is
 defined however, +rails/engine+ is also loaded, which is responsible for
 handling the behavior and definitions of Rails engines.
 
-TIP: You can read more about engines in the "Getting Started with Engines":engines.html
-guide.
+TIP: You can read more about engines in the "Getting Started with Engines":engines.html guide.
 
 Among other things, Rails Engine is also responsible for loading the
 Railtie class.
@@ -678,7 +656,7 @@ h4. +activesupport/lib/active_support/deprecation/proxy_wrappers.rb+
 +proxy_wrappers.rb+ defines deprecation wrappers for methods, instance variables and constants. Previously, this was used for the +RAILS_ENV+ and +RAILS_ROOT+ constants for 3.0 but since then these constants have been removed. The deprecation message that would be raised from these would be something like:
 
 <plain>
-  BadConstant is deprecated! Use GoodConstant instead.
+BadConstant is deprecated! Use GoodConstant instead.
 </plain>
 
 h4. +active_support/ordered_options+
@@ -689,7 +667,7 @@ The next file required is +active_support/core_ext/hash/deep_dup+ which is cover
 
 h4. +active_support/core_ext/object+
 
-This file is responsible for requiring many more core extensions:
+This file is responsible for requiring many more Active Support core extensions:
 
 <ruby>
 require 'active_support/core_ext/object/acts_like'
@@ -947,7 +925,7 @@ The +initializers_chain+ method referenced in the +initializers_for+ method is d
 <ruby>
 def initializers_chain
   initializers = Collection.new
- ancestors.reverse_each do | klass |
+  ancestors.reverse_each do |klass|
     next unless klass.respond_to?(:initializers)
     initializers = initializers + klass.initializers
   end
@@ -1010,46 +988,35 @@ This file defines the +ActiveSupport::Railtie+ constant which like the +I18n::Ra
 
 Then this Railtie sets up three more initializers:
 
-* +active_support.initialize_whiny_nils+
 * +active_support.deprecation_behavior+
 * +active_support.initialize_time_zone+
+* +active_support.set_configs+
 
 We will cover what each of these initializers do when they run.
 
 Once the +active_support/railtie+ file has finished loading the next file required from +railties/lib/rails.rb+ is the +action_dispatch/railtie+.
 
-h4. +activesupport/lib/action_dispatch/railtie.rb+
+h4. +actionpack/lib/action_dispatch/railtie.rb+
 
 This file defines the +ActionDispatch::Railtie+ class, but not before requiring +action_dispatch+.
 
-h4. +activesupport/lib/action_dispatch.rb+
-
-This file attempts to locate the +active_support+ and +active_model+ libraries by looking a couple of directories back from the current file and then adds the +active_support+ and +active_model+ +lib+ directories to the load path, but only if they aren't already, which they are.
-
-<ruby>
-activesupport_path = File.expand_path('../../../activesupport/lib', __FILE__)
-$:.unshift(activesupport_path) if File.directory?(activesupport_path) && !$:.include?(activesupport_path)
-
-activemodel_path = File.expand_path('../../../activemodel/lib', __FILE__)
-$:.unshift(activemodel_path) if File.directory?(activemodel_path) && !$:.include?(activemodel_path)
-</ruby>
-
-In effect, these lines only define the +activesupport_path+ and +activemodel_path+ variables and nothing more.
+h4. +actionpack/lib/action_dispatch.rb+
 
-The next two requires in this file are already done, so they are not run:
+This file starts off with the following requires:
 
 <ruby>
 require 'active_support'
 require 'active_support/dependencies/autoload'
+require 'active_support/core_ext/module/attribute_accessors'
 </ruby>
 
-The following require is to +action_pack+ (+activesupport/lib/action_pack.rb+) which has a 22-line copyright notice at the top of it and ends in a simple require to +action_pack/version+. This file, like other +version.rb+ files before it, defines the +ActionPack::VERSION+ constant:
+The following require is to +action_pack+ (+actionpack/lib/action_pack.rb+) which contains a simple require to +action_pack/version+. This file, like other +version.rb+ files before it, defines the +ActionPack::VERSION+ constant:
 
 <ruby>
 module ActionPack
   module VERSION #:nodoc:
-    MAJOR = 3
-    MINOR = 1
+    MAJOR = 4
+    MINOR = 0
     TINY  = 0
     PRE   = "beta"
 
@@ -1067,8 +1034,8 @@ This file makes a require to +active_model/version+ which defines the version fo
 <ruby>
 module ActiveModel
   module VERSION #:nodoc:
-    MAJOR = 3
-    MINOR = 1
+    MAJOR = 4
+    MINOR = 0
     TINY  = 0
     PRE   = "beta"
 
@@ -1105,7 +1072,7 @@ Once it has finished loading, the +I18n.load_path+ method is used to add the +ac
 
 The loading of this file finishes the loading of +active_model+ and so we go back to +action_dispatch+.
 
-h4. Back to +activesupport/lib/action_dispatch.rb+
+h4. Back to +actionpack/lib/action_dispatch.rb+
 
 The remainder of this file requires the +rack+ file from the Rack gem which defines the +Rack+ module. After +rack+, there's autoloads defined for the +Rack+, +ActionDispatch+, +ActionDispatch::Http+, +ActionDispatch::Session+. A new method called +autoload_under+ is used here, and this simply prefixes the files where the modules are autoloaded from with the path specified. For example here:
 
@@ -1119,7 +1086,7 @@ The +Assertions+ module is in the +action_dispatch/testing+ folder rather than s
 
 Finally, this file defines a top-level autoload, the +Mime+ constant.
 
-h4. Back to +activesupport/lib/action_dispatch/railtie.rb+
+h4. Back to +actionpack/lib/action_dispatch/railtie.rb+
 
 After +action_dispatch+ is required in this file, the +ActionDispatch::Railtie+ class is defined and is yet another class that inherits from +Rails::Railtie+. This class defines some initial configuration option defaults for +config.action_dispatch+ before setting up a single initializer called +action_dispatch.configure+.
 
@@ -1141,22 +1108,21 @@ h4. +activerecord/lib/active_record.rb+
 
 This file begins by detecting if the +lib+ directories of +active_support+ and +active_model+ are not in the load path and if they aren't then adds them. As we saw back in +action_dispatch.rb+, these directories are already there.
 
-The first three requires have already been done by other files and so aren't loaded here, but the 4th require, the one to +arel+ will require the file provided by the Arel gem, which defines the +Arel+ module.
+The first couple of requires have already been done by other files and so aren't loaded here, but the next one to +arel+ will require the file provided by the Arel gem, which defines the +Arel+ module.
 
 <ruby>
 require 'active_support'
-require 'active_support/i18n'
 require 'active_model'
 require 'arel'
 </ruby>
 
-The 5th require in this file is one to +active_record/version+ which defines the +ActiveRecord::VERSION+ constant:
+The file required next is +active_record/version+ which defines the +ActiveRecord::VERSION+ constant:
 
 <ruby>
 module ActiveRecord
   module VERSION #:nodoc:
-    MAJOR = 3
-    MINOR = 1
+    MAJOR = 4
+    MINOR = 0
     TINY  = 0
     PRE   = "beta"
 
@@ -1180,7 +1146,9 @@ This will set the engine for +Arel::Table+ to be +ActiveRecord::Base+.
 The file then finishes with this line:
 
 <ruby>
-I18n.load_path << File.dirname(__FILE__) + '/active_record/locale/en.yml'
+ActiveSupport.on_load(:i18n) do
+  I18n.load_path << File.dirname(__FILE__) + '/active_record/locale/en.yml'
+end
 </ruby>
 
 This will add the translations from +activerecord/lib/active_record/locale/en.yml+ to the load path for +I18n+, with this file being parsed when all the translations are loaded.