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I am completely new to C++ and am trying to write an extremely basic program, but I am having issues with initializing an integer.

is not type safe. For historical reason it was defined as 0 without casting, and the compiler silence warning of casting number to pointer on this special zero. For instant, you can do: but not this without implicit casting: the side effect is that it can be abused as number values, as other answer mentioned. improve this by enforcing it is a pointer, you can't assign this to an integer. Since the behaviour is changed, a new name is created for backward compatibility.

Just in case my question leaves any room for miscommunication, theres the code example. If was not templated but inherited from directly then the sample would fail to compile because clearly function attempts to call a function on base class which is non-existent. However if is templated then this is only picked up if is actually called. I'd like to know why there is this difference. In both instances would be dead code and stripped anyway, yet the program is ill-formed in the non-template scenario.