c++ - 分析这句CPP代码：typedef action_t* (*rule_t)(const sandbox_t*, const event_t*, action_t*);

Question

在分析一个源码源码的时候看到了这么一句话：

typedef action_t* (*rule_t)(const sandbox_t*, const event_t*, action_t*);

。。。然后我就晕了。。。

呃。。。仔细看了看。。然后就明白了……
就是说一个叫做action_t类型的东西是个函数指针。。。(rule_t)是返回值类型，(const sandbox_t*, const event_t*, action_t*)是参数表

Answer 1

rule_t is the name of typedef, which represents

返回值是action_t*， 参数是(const sandbox_t*, const event_t*, action_t*)的函数指针类型

Answer 2

Obviously not what you said!

action_t* is the return type
rule_t is the name of the function pointer
The following is the parameter table

In fact, we shouldn’t say that. We should say that rule_t is a function pointer, and the signature of the function it points to is similar to the following:

action_t* func(const sandbox_t*, const event_t*, action_t*);