宏增加值然后连接
我想创建一个递归宏来创建下一个"类.
I want to create a recursive Macro the will create the "next" class.
例子:
#define PRINTME(indexNum) class m_##(indexNum+1) { }
indexNum + 1 被评估为 int，并且不会连接到类名.
The indexNum + 1 is evaluated as an int, and won't concatenate to the class name.
如何让编译器在连接之前对其进行评估?
How can I cause the compiler to evaluate that, before concatenating?
推荐答案
简单的答案是你不能.预处理器一般处理文本和标记；唯一的算术是在 #if 和 #elif 指令中进行的.
The simple answer is that you can't. The preprocessor generally deals in text and tokens; the only place arithmetic is carried out in in #if and #elif directives.
此外，宏扩展不是递归的.在扩展过程中，正在扩展的宏被禁用，并且不可用于进一步替换.
Also, macro expansion isn't recursive. During expansion, the macro being expanded is disabled, and is not available for further substitution.
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