ruby - 使用私有(private) attr_accessor 时，为什么 self.attribute= 起作用，而 self.attribute 不起作用？

Question

假设我有一个类，我在其中定义了一个 attr_accessor，如下所示:

private

attr_accessor :attribute

我理解为什么使用 self.attribute 读取器方法不起作用 - 在 Ruby 中，您不能在显式接收器上调用私有(private)方法。

令我困惑的是，为什么这条规则不适用于作者？为什么我可以调用 self.attribute = 1，并且不会引发任何访问冲突错误？

Answer 1

根据@Jörg W Mittag 对 Alan Skorkin 博客条目的评论 Ruby Access Control – Are Private And Protected Methods Only A Guideline? :

Quick note: there is a special case where calling private methods with an explicit receiver is allowed:

If the method name ends with '=' (i.e. it is an attribute writer) and the explicit receiver is 'self', then this works. This is necessary, because setters can only be called with an explicit receiver because of the method/variable ambiguity. Otherwise it wouldn't be possible to call private setters.

Jörg 没有引用任何消息来源，但他非常可靠。