refactor, data to object

data_to_object.rb

class CarryBack
    def initialize
        @buy_list = []
    end

    def add_item(price)
        @buy_list.push price
    end

    def total
        @buy_list.inject(0, :+)
    end
end

c = CarryBack.new

c.add_item 100
c.add_item 200
p c.total


class Item
    @@price = 0

    def tax
        @@price * 1.05
    end

    def get_price
        @@price
    end
end

class Meat < Item
    @@name = "肉"
    @@price = 200
end

class Rice < Item
    @@name = "米"
    @@price = 1000
end

class CarryBack2 < CarryBack
    def add_item(obj)
        @buy_list.push obj
    end

    def total_include_tax
        @buy_list.inject(0){|sum, i| sum += i.tax}.to_i
    end

    def total
        @buy_list.inject(0){|sum, i| sum += i.get_price}
    end
end

c2 = CarryBack2.new
c2.add_item Rice.new
p c2.total
p c2.total_include_tax