POD stands for Plain Old Data – that is, a class (whether defined with the keyword struct or the keyword class) without constructors, destructors and virtual members functions. Wikipedia’s article on POD goes into a bit more detail and defines it as: A Plain Old Data Structure in C++ is an aggregate class that contains … Read more
class A { public: int x; protected: int y; private: int z; }; class B : public A { // x is public // y is protected // z is not accessible from B }; class C : protected A { // x is protected // y is protected // z is not accessible from … Read more
The differences between a class and a struct in C++ is: struct members and base classes/structs are public by default. class members and base classes/struts are private by default. Both classes and structs can have a mixture of public, protected and private members, can use inheritance and can have member functions. I would recommend you: … Read more
(See here also for my C++11 answer) In order to parse a C++ program, the compiler needs to know whether certain names are types or not. The following example demonstrates that: t * f; How should this be parsed? For many languages a compiler doesn’t need to know the meaning of a name in order … Read more
Here is how I understood not just what virtual functions are, but why they’re required: Let’s say you have these two classes: class Animal { public: void eat() { std::cout << “I’m eating generic food.”; } }; class Cat : public Animal { public: void eat() { std::cout << “I’m eating a rat.”; } }; … Read more
I guess this document might serve as a not so short introduction : n3055 The whole massacre began with the move semantics. Once we have expressions that can be moved and not copied, suddenly easy to grasp rules demanded distinction between expressions that can be moved, and in which direction. From what I guess based … Read more
Working for about 4-5 years with software/firmware development and environment testing of miniaturized satellites*, I would like to share my experience here. *(miniaturized satellites are a lot more prone to single event upsets than bigger satellites due to its relatively small, limited sizes for its electronic components) To be very concise and direct: there is … Read more
It seems you (and/or your company) have a fundamental misunderstanding of what a family tree is supposed to be. Let me clarify, I also work for a company that has (as one of its products) a family tree in its portfolio, and we have been struggling with similar problems. The problem, in our case, and … Read more
Welcome to the world of denormalized floating-point! They can wreak havoc on performance!!! Denormal (or subnormal) numbers are kind of a hack to get some extra values very close to zero out of the floating point representation. Operations on denormalized floating-point can be tens to hundreds of times slower than on normalized floating-point. This is … Read more