Question

The following code doesn’t work:

class String{
public:
    char* str;
    int* counter;

    String(){
        str = NULL;
        counter = new int;
        *counter = 1;
    };
    String(const char* str1){
        String();
        str = new char[strlen(str1)+1];
        strcpy(str, str1);
    };


 };

I’ve changed the call to the empty constructor and replaced it with its internals, and now the following code works:

class String{
public:
    char* str;
    int* counter;

    String(){
        str = NULL;
        counter = new int;
        *counter = 1;
    };
    String(const char* str1){
        //String();
        str = new char[strlen(str1)+1];
        strcpy(str, str1);
        counter = new int;
        *counter = 1;
    };

Can you please suggest why?

Thanks, Li.

Answer 1

“Doesn’t work” is not a good description of the problem. But you apparently tried to invoke a constructor from another one. That’s called constructor delegation and is not (yet) supported by C++.

BTW, a class like this should get a user-defined copy constructor, assignment operator and destructor.