or, you know, something similar. Nice website, I’ve learnt more here than in my university. They insist on “taking it slow” by teaching nothing more complex than pointers. You know, really incredibly abstract things like object oriented programming that only gurus and wise old men can know. I’m lucky they aren’t trying to ease me into c by teaching me pascal first (they did that up to this year).

“In the absense of an initializing line, C++ will initialize the value to 0.”?

In 4.2 you said not to use global variables:

“2) To hold data that needs to be used by the entire program (eg. configuration settings).”
(that’s what i’d need to do)

“there are better ways to do #2 (eg. static classes).”
Still, I didn’t found anything like “static classes” in later lessons. Did you mean this? (classes with static members) Although, from your examples, ’static’ seems to serve an entirely different purpose in classes, then the one mentioned above in 2)

For example, let’s say s_nID is 0. The value 0 is copied into a temp variable. s_nID is incremented to 1. Then the value 0 is returned.

All of this happens transparently when you use the postfix ++ operator. That’s why using the prefix ++ operator can be more efficient.

int Something::s_nValue

happened to evaluate to 0 was probably circumstantial in the same way that

int nX;

will probably be 0, but it’s not guaranteed.

1
2
3

 int Something::s_nValue=1;

. i.e.

#include <iostream>
class Something
{
public:
    static int s_nValue;
};

//int Something::s_nValue;

int main()
{
    Something cFirst;

    Something cSecond;
    std::cout << cSecond.s_nValue;

    return 0;
}

I got a compilation error:

…/main.cpp|15|undefined reference to `Something::s_nValue’|.

I also tried

 int Something::s_nValue;

Note that there is no “=1″ this time, and everything works out fine with s_nValue=0;
Does this mean

 int Something::s_nValue;

is always needed when we declare a static variable of a class? By the way, I am using Code::Blocks with GCC as the compiler on my Ubuntu.