Collection Proxy

	require "delegate"
	class CollectionProxy
	def products
	@products ||= HasManyAssociation.new([])
	@products.associated_class ||= Product
	@products
	end
	end
	class Product
	def initialize(attributes)
	@attributes = attributes
	end
	attr_reader :attributes
	def name
	attributes[:name]
	end
	end
	# -----------------------------------------------------------
	# With DelegateClass
	# -----------------------------------------------------------
	class HasManyAssociation < DelegateClass(Array)
	attr_accessor :associated_class
	def initialize(array)
	super(array)
	end
	def create(params)
	self << associated_class.new(params)
	end
	end
	proxy = CollectionProxy.new
	products = proxy.products
	products.create(:name => 'products one')
	products.create(:name => 'products two')
	p products[0].name
	p products[1].name
	p products.map { |q| q.name }
	# -----------------------------------------------------------
	# with method_missing
	# -----------------------------------------------------------
	class HasManyAssociation < BasicObject
	attr_accessor :associated_class
	def initialize(array)
	@array = array
	end
	def create(params)
	self << associated_class.new(params)
	end
	def method_missing(*a, &b)
	@array.send(*a, &b)
	end
	end
	proxy = CollectionProxy.new
	products = proxy.products
	products.create(:name => 'products one')
	products.create(:name => 'products two')
	p products.map { |q| q.name }

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