letsstudy

When a construct throws an exception then; that object is not fully constructed so destructor can not be called on that object. c++ destroys only fully constructed objects So this may leads to memory leakage. To solve this problem we have to 1. write a cleanup function which clears all allocated memory or resource 2. write the part of constructor block which  may leads to crash in try block & call cleanup function in catch block. #include<iostream> using namespace std; class first {     public:         first()         {             cout<<"in constructor of first"<<endl;         }         ~first()         {             cout<<"in destructor of first"<<endl;       ...

The syntax of copy constructor says that it should be reference not pointer. 1. Passing by references ensures an actual object is passed to the copy constructor, while a pointer can have NULL value, and make the constructor fail. 2. if we pass a pointer then we have to dereference it. so it will be overhead for the user. Technically we can write a constructor which pass a pointer; but that is overloaded constructor not copy constructor.