// Consider an actual class.
class Obj {
static int i, j;
public:
void f() const { cout << i++ << endl; }
void g() const { cout << j++ << endl; }
};
// Static member definitions:
int Obj::i = 10;
int Obj::j = 12;
// Implement a container for the above class
class ObjContainer {
vector<Obj*> a;
public:
void add(Obj* obj) {
a.push_back(obj); // call vector's standard method.
}
friend class SmartPointer;
};
// implement smart pointer to access member of Obj class.
class SmartPointer {
ObjContainer oc;
int index;
public:
SmartPointer(ObjContainer& objc) {
oc = objc;
index = 0;
}
// Return value indicates end of list:
bool operator++() { // Prefix version
if(index >= oc.a.size()) return false;
if(oc.a[++index] == 0) return false;
return true;
}
bool operator++(int) { // Postfix version
return operator++();
}
// overload operator->
Obj* operator->() const {
if(!oc.a[index]) {
cout << Zero value;
return (Obj*)0;
}
return oc.a[index];
}
};
int main() {
const int sz = 10;
Obj o[sz];
ObjContainer oc;
for(int i = 0; i < sz; i++) {
oc.add(&o[i]);
}
SmartPointer sp(oc); // Create an iterator
do {
sp->f(); // smart pointer call
sp->g();
} while(sp++);
return 0;
}
版权声明:本文内容由互联网用户自发贡献,该文观点与技术仅代表作者本人。本站仅提供信息存储空间服务,不拥有所有权,不承担相关法律责任。如发现本站有涉嫌侵权/违法违规的内容, 请发送邮件至 dio@foxmail.com 举报,一经查实,本站将立刻删除。