C++ 动态新闻推送 第24期

struct a {
  int field1;
  struct {
    int field_2;
    int field_3;
  } sub;
};

#define field2 sub.field_2
#define field2 sub.field_3

struct a {
  int field1;
  union {
    struct {
      int field2;
      int field3;
    };
    struct {
      int field2;
      int field3;
    } sub;
  };
};

#include <cstdio>

auto main() -> int {
  std::puts("Hello world");        // during run-time
  @meta std::puts("Hello circle"); // during compilation-time
}

Hello circle
ASM generation compiler returned: 0
Hello circle
Execution build compiler returned: 0
Program returned: 0
Hello world

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