In rails how can I delegate to a class method

ruby-on-rails, ruby-on-rails-3

Solution

You're picking up the ActiveSupport delegation core extension. The `delegate` helper defines an instance method for the current class so that instances of it delegate calls to some variable on that instance.

If you want to delegate at the class level, you need to open up the singleton class and set up the delegation there:

class Important < ActiveRecord::Base
  attr_accessible :email

  has_one :task, :as => :taskable, :dependent => :destroy

  class << self
    delegate :this_week, :to => :task
  end
end

But this assumes that `Important.task` is a reference to the `Task` class (which it is not)

Rather than relying on the delegation helper, which is just going to make your life difficult, I'd suggest explicit proxying here:

class Important < ActiveRecord::Base
  attr_accessible :email

  has_one :task, :as => :taskable, :dependent => :destroy

  class << self
    def this_week(*args, &block)
      Task.this_week(*args, &block)
    end
  end
end

Problem

``` class Task < ActiveRecord::Base attr_accessible :due_date, :text def self.this_week where(:due_date => Date.today.beginning_of_week..Date.today.end_of_week) end end class Important < ActiveRecord::Base attr_accessible :email has_one :task, :as => :taskable, :dependent => :destroy delegate this_week, :to => :task end ``` So far this delegate is not working as expected, when I try `Important.this_week`. I get an error saying there is no method `this_week` defined for class... Any ideas? Can I even delegate to a class method like this? I may have another class or two extending `Task` in this way, so I'm curious how this works in a way that doesn't duplicate a bunch of code to each implementing class.

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