The Tips of Hidden Structure Pointer in Macro Definition in C Language

1. Hiding pointer passing through macro definition

definition:

#define vector_push_back(v, e)  _vector_push_back(v, (void *)&e, sizeof(e))

 void _vector_push_back(struct vector *v, void *e, size_t type_size)

use: 

struct tmp_box tb;

tb.c = 'a';

vector_push_back(c, tb);

You can see that the structure object is directly passed when using it, and there is no need to pass the pointer of the structure. Convenient!