C++ const question

Question

If I do this:

// In header 
class Foo {
void foo(bar*);
};

// In cpp
void Foo::foo(bar* const pBar) {
//Stuff
}

The compiler does not comp

Answer 1

In the former, the const doesn't affect the interface, only the implementation. You are saying to the compiler, "I am not going to change the value of the bar* within this function". You can still change what is pointed to by the pointer. In the latter, you are telling the compiler (and all callers) that you will not change the bar structure that the bar* points to.