extern用法相关解决思路

extern用法相关

C/C++ code

文件A：/* A.h */#ifndef _A_CPP#define _A_CPP#include "B.h"extern Test t;#endif/* A.cpp */int main(){   ...   t.set(path);   ...}/* B.h */class Test {  public:  TTT(..);  set(std::string path)  {this->path = path};  private:  std::string path;} t;/* B.cpp */{  TTT(..){...}}