看看这个由于包含关系过于复杂而编译出错的问题吧
/////////////////////main.cpp////////////////int main(int argc, char **argv){ return 1;}/////////////////////base.h////////////////#pragma onceclass base{protected: base();};/////////////////////curve.h////////////////#pragma once#include "base.h"class curve : public base{protected: curve();};/////////////////////curveCollection.h////////////////#pragma once#include "base.h"class curveCollection : public base{protected: curveCollection();};/////////////////////curveCollection.cpp////////////////#include "curvecollection.h"#include "curve.h"curveCollection::curveCollection() // 此处报错 undefined reference to `base::base(){}