How to correctly inherit std::iterator.

Question

Guys if I have class like below:

template<class T>
class X
{
T** myData_;
public:
class iterator : public iterator<random_access_iterator_tag,/*WHAT SHALL I PUT HERE? T OR T** AND WHY?*/>
{
T** itData_;//HERE I'M HAVING THE SAME TYPE AS MAIN CLASS ON WHICH ITERATOR WILL OPERATE
};
};

Questions are in code next to appropriate lines.
Thank you.

Answer 1

As for the first question, that should be the data type the iterator returns. Presumably T.

As for the second, it depends completely upon what your iterator actually does, which isn't definite or obvious from the information given.

Note that std::iterator doesn't define any operations for you, it only defines some typedefs which you can inherit.

Answer 2

As a starting point, your value type should be the type of object your container holds. My guess would be either T or T*, you don't really provide enough information to say. See here for an explanation of what the various parameters mean. The rest can often be left as defaults.

Answer 3

Unless you just really want to learn this stuff, I'd suggest using Boost.Iterator