Ruby - 从对象内部调用 setter [英] Ruby - Calling setters from within an object

问题描述

我一直在阅读 Pragmatic Programmers 'Programming Ruby' 一书，想知道是否可以在类中调用 setter 方法而不是直接分配给实例变量.

I've been working through the Pragmatic Programmers 'Programming Ruby' book and was wondering if it was possible to call a setter method within a class rather than just assigning to the instance variable directly.

class BookInStock

  attr_reader :isbn, :price

  def initialize (isbn, price)
    @isbn = isbn
    @price = Float(price)
  end

  def price_in_cents
    Integer(price*100 + 0.5)
  end

  def price_in_cents=(cents)
    @price = cents/100.0
  end

  def price=(dollars)
    price = dollars if dollars > 0
  end

end

在这种情况下，我使用 setter 来确保价格不能为负数.我想知道的是，是否可以从 price_in_cents 设置器中调用价格设置器，这样我就不必编写额外的代码来确保价格为正数.

In this case I am using a setter to ensure that the price can't be negative. What i want to know is if it is possible to call the price setter from within the price_in_cents setter so that I wont have to write extra code to ensure that the price will be positive.

提前致谢

推荐答案

使用self.setter，即:

def price_in_cents=(cents)
    self.price = cents/100.0
end

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