How to check if the iterator is initialized?

Question

If I use a default constructor for an iterator, how to check if it was assigned later on?

For pointers, I could do this :

int *p = NULL;
/// some code
         


        

Answer 1

This question has already been treated in Stackoverflow. The quintessence is that the default constructor initializes an iterator to a singular value, and the only addmissible operation on it is to assign it another iterator value. In particular it is not possible to query the value of such unitialized iterator. Therefore it is a good programming practice to initialize the iterator to a specific value of a specific container, which then can be tested for.