如何将现有的named_scope添加到匿名范围？

Question

我有一个模特：

class Shirt < ActiveRecord::Base
  named_scope :red, :conditions => { :color => 'red' }
  named_scope :blue, :conditions => { :color => 'blue' }
  named_scope :xl,  :conditions => { :size  => 'xl'  }
end

我忘了，如何轻松地将命名范围添加到现有的匿名范围：

scope = Shirt.scoped({})
#and how to add ie. :red to scope?

Answer 1

Shirt.scoped({}).red？

Answer 2

这可以通过以下代码实现：

named_scope :colour, lambda { |colour_id| {:conditions => ["colour_id = ?", colour_id])}}

您可以链接命名范围：

Shirt.red.xl