objective-c - Objective-C weakself declaration

Question

I was looking through some Apple sample code for their 2014 WWDC session 'Advanced User Interfaces with Collection Views' and came across a weakself declaration that looked like the following:

__weak typeof(&*self) weakself = self;

My question is: what do the &* mean in the declaration? Why not just have:

__weak typeof(self) weakself = self;

Thanks for your help.

Answer 1

为什么不只是有：

__weak typeof(self) weakself = self;

你可以。这是正常的做法。一些以前版本的编译器没有正确处理它，但很久以前就修复了。

Answer 2

self是一个MyInstance *。当你说*self的时候，你是在取消对self*返回的引用self。然后，当您使用时，&(*self)您将获取内存地址。