module ActionController::Helpers::ClassMethods  
        
        Public instance methods
Declares helper accessors for controller attributes. For example, the following adds new name and name= instance methods to a controller and makes them available to the view: attr_accessor :name helper_attr :name
Parameters
- 
attrs- Names of attributes to be converted into helpers. 
Source code GitHub
# File actionpack/lib/action_controller/metal/helpers.rb, line 84
def helper_attr(*attrs)
  attrs.flatten.each { |attr| helper_method(attr, "#{attr}=") }
end
            Provides a proxy to access helper methods from outside the view.
Note that the proxy is rendered under a different view context. This may cause incorrect behavior with capture methods. Consider using helper instead when using capture.
Source code GitHub
# File actionpack/lib/action_controller/metal/helpers.rb, line 94
def helpers
  @helper_proxy ||= begin
    proxy = ActionView::Base.empty
    proxy.config = config.inheritable_copy
    proxy.extend(_helpers)
  end
end
            Override modules_for_helpers to accept :all as argument, which loads all helpers in helpers_path.
Parameters
- 
args- A list of helpers 
Returns
- 
array- A normalized list of modules for the list of helpers provided. 
Source code GitHub
# File actionpack/lib/action_controller/metal/helpers.rb, line 112
def modules_for_helpers(args)
  args += all_application_helpers if args.delete(:all)
  super(args)
end