定义类型的正确方法(typedef与#define) [英] Proper way to define type (typedef vs #define)

问题描述

以下哪种方法在定义变量类型时更安全?我知道看到#defines时我们都会皱眉，但这似乎和typedef一样有效:

Which of these methods is more secure for defining variable types? I know that we all frown when we see #defines, but it seems to work just as well as typedef here:

一种方法或另一种方法有优势吗?如果可以，那会是什么?

Is there an advantage one way or the other, and if so what might it be?

方法一:

    #include <iostream>

    #define byte unsigned char

    int main() {
        byte testByte = 'A';
        std::cout << testByte << std::endl;

        return 0;
    }

方法二:

     #include <iostream>

     int main() {
        typedef unsigned char byte;

        byte testByte = 'A';
        std::cout << testByte << std::endl;

        return 0;
    }

推荐答案

您应始终使用第二个(即typedef 或使用).

You should always use the 2nd one (i.e. typedef or using).

尽量不要在c ++中使用宏，并且可以避免大多数情况.它们只是在编译之前替换文本，更危险".例如

Try to not use macros in c++ as far as possible, and most cases could be avoided. They're just text replacement before compiling, and more "dangerous". e.g.

#define byte_pointer unsigned char*
byte_pointer p, q; // only p is a pointer

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