如何將現有的named_scope添加到匿名作用域？

Question

我有一個模型：

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，如何輕鬆命名範圍添加到現有的匿名範圍：

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

Answer 1

這可以用下面的代碼來實現：

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

您可以鏈式命名示波器：

Shirt.red.xl 

Answer 2

Shirt.scoped({}).red？