有宏的任何好的用途吗？ [英] Are there any good uses of macros?

问题描述

据我所知，宏在编译器甚至看到它之前重新排列程序文本，从而潜在地导致问题。我几乎看不到他们在C ++代码，大多在C。

As far as I know, macros rearrange the program text before the compiler even sees it properly, thus potentially causing problems. I hardly ever see them in C++ code, mostly in C.

我知道的唯一的好用，是包含保护（ #ifndef ）。

The only good use I know of, is inclusion guards (#ifndef).

需要还有其他要做的宏，不能以更清晰的方式实现？ / p>

Is there anything else that needs to be done with macros and cannot be implemented in a cleaner way?

推荐答案

记录和例外。

宏允许您轻松捕获 __ FILE __ ， __ LINE __ 和 __func __ 。确保你可以每次手动编写它们，但坦率地说，这是单调乏味和容易出错（ __ FILE __ 和 __ func __ C字符串，所以你有风险混合起来）。

A macro allows you to effortlessly capture __FILE__, __LINE__ and __func__. Oh sure you could write them manually each time, but frankly this is tedious and error prone (both __FILE__ and __func__ are C-string so you risk mixing them up).

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