问题描述
在此文档中在标有变量限定符"的部分下，苹果说:
In this document, under the section labeled "Variable Qualifiers", Apple says:
ClassName * qualifier variableName;
MyClass * __weak myWeakReference;
MyClass * __unsafe_unretained myUnsafeReference;
看cdecl.org并不能澄清任何事情.谁能解释他们所指的问题"?换句话说，请帮助我说服其他人，这实际上很重要，而不仅仅是因为这个自述文件这么说."
Looking at cdecl.org doesn't clarify anything. Can anyone explain what "the issue" they are referring to is? In other words, help me convince others that this actually matters in a way that isn't just "because this one readme says so."
推荐答案
查看我的带有乱码的英语翻译示例
See my examples with gibberish to English translations
众所周知，
ClassName * const varName; //varName is a constant pointer to ClassName
与
const ClassName * varName; //varName is a pointer to constant ClassName
或
ClassName const * varName; //varName is a pointer to constant ClassName
以同样的方式声明
ClassName * __weak varName; //varName is a weak pointer to ClassName
此声明
__weak ClassName * varName; //varName is a pointer to weak?? ClassName??
非常不同.但是，第二个含义很明确(尽管从技术上讲是不正确的)，编译器可以原谅".
are VERY different. However, the meaning of the second one is clear (although it's technically incorrect) and it can be "forgiven" by the compiler.
一旦您开始使用指向指针的指针(例如Foo * __autoreleasing *)，正确性就变得更为重要.
The correctness is a bit more important once you start working with pointers to pointers (e.g. Foo * __autoreleasing *).
我认为他们想保护初学者免受C/C ++声明的干扰.一开始就有预选赛似乎很自然.
I assume they wanted to protect beginner developers from the C/C++ declaration gibberish. Having the qualifier in the beginning seems more natural.
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