AR DRY scoping of the nested models

dry_scope.rb

class Collection < ActiveRecord::Base
  has_many :products
  scope :live,  where("collections.end_date IS NOT NULL AND collections.end_date >= ?", Time.now.to_date)
end

class Product < ActiveRecord::Base
  belongs_to :collection
  
  # how to DRY this .where ?
  scope :launched, joins(:collection).where("collections.end_date IS NOT NULL AND collections.end_date >= ?", Time.now.to_date)
end

# usage:
Product.launched
# Product scope which belongs_to Collection.live

da, znam za lambda, ali, naravno da smetnem s uma kad najviše treba ... :-)