Is is a good practice to put the definition of C++ classes into the header file?

Question

When we design classes in Java, Vala, or C# we put the definition and declaration in the same source file. But in C++ it is traditionally preferred to separate the definitio

Answer 1

The biggest difference is that every function is declared as an inline function. Generally your compiler will be smart enough that this won't be a problem, but worst case scenario it will cause page faults on a regular basis and make your code embarrassingly slow. Usually the code is separated for design reasons, and not for performance.