1 files changed, 32 insertions, 19 deletions

diff --git a/actionpack/lib/action_controller/abstract/helpers.rb b/actionpack/lib/action_controller/abstract/helpers.rb
index 1f0b38417b..43832f1e2d 100644
--- a/actionpack/lib/action_controller/abstract/helpers.rb
+++ b/actionpack/lib/action_controller/abstract/helpers.rb
@@ -1,19 +1,14 @@
 module AbstractController
   module Helpers
+    extend ActiveSupport::Concern
+
     depends_on Renderer
-    
-    setup do
+
+    included do
       extlib_inheritable_accessor :master_helper_module
       self.master_helper_module = Module.new
     end
-  
-    # def self.included(klass)
-    #   klass.class_eval do
-    #     extlib_inheritable_accessor :master_helper_module
-    #     self.master_helper_module = Module.new
-    #   end
-    # end
-    
+
     def _action_view
       @_action_view ||= begin
         av = super
@@ -21,19 +16,38 @@ module AbstractController
         av
       end
     end
-    
+
     module ClassMethods
       def inherited(klass)
         klass.master_helper_module = Module.new
         klass.master_helper_module.__send__ :include, master_helper_module
-        
+
         super
       end
-      
+
+      # Makes all the (instance) methods in the helper module available to templates rendered through this controller.
+      # See ActionView::Helpers (link:classes/ActionView/Helpers.html) for more about making your own helper modules
+      # available to the templates.
       def add_template_helper(mod)
         master_helper_module.module_eval { include mod }
       end
-      
+
+      # Declare a controller method as a helper. For example, the following
+      # makes the +current_user+ controller method available to the view:
+      #   class ApplicationController < ActionController::Base
+      #     helper_method :current_user, :logged_in?
+      #
+      #     def current_user
+      #       @current_user ||= User.find_by_id(session[:user])
+      #     end
+      #
+      #      def logged_in?
+      #        current_user != nil
+      #      end
+      #   end
+      #
+      # In a view:
+      #  <% if logged_in? -%>Welcome, <%= current_user.name %><% end -%>
       def helper_method(*meths)
         meths.flatten.each do |meth|
           master_helper_module.class_eval <<-ruby_eval, __FILE__, __LINE__ + 1
@@ -43,17 +57,16 @@ module AbstractController
           ruby_eval
         end
       end
-      
-      def helper(*args, &blk)
+
+      def helper(*args, &block)
         args.flatten.each do |arg|
           case arg
           when Module
             add_template_helper(arg)
           end
         end
-        master_helper_module.module_eval(&blk) if block_given?
+        master_helper_module.module_eval(&block) if block_given?
       end
     end
-    
   end
-end
\ No newline at end of file
+end