将块指令作为C中的宏参数传递 [英] pass block instruction as macro's argument in C

问题描述

我不知道这是否可行，我想像参数一样在宏中传递指令块.我将向您展示一个示例:

I don't know if that is possible, I want to pass a block of instructions in macro like an argument.I will show you an example:

#define ADD_MACRO(size, BLOCK){ for(int i=0; i<size; i++){\
                                    BLOCK} }

您怎么看?

感谢帮助

推荐答案

给定宏的唯一问题是它不处理BLOCK中的逗号.可变参数宏参数允许使用逗号:

The only problem with the given macro is that it doesn't handle commas in the BLOCK. Commas are tolerated by a variadic macro parameter:

#define ADD_MACRO(size, ...) do { for(int i=0; i<size; i++){\
                                      __VA_ARGS__} } while(0)

(此外，通常的做法是将语句宏包含在do … while(0)中，以强制用户包括分号.)

(Also, common practice is to enclose statement macros in do … while(0) to force the user to include a semicolon.)

(当然，最初的问题可能有更好的解决方案.预处理器是一种钝器.这是针对所述问题的预处理器解决方案.)

(Of course, the original problem may have a better solution. The preprocessor is a blunt instrument. This is the preprocessor solution to the stated question.)

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