What is the difference between const virtual and virtual const?

Question

I saw that some function in C++ was declared as

virtual const int getNumber();

But what is the difference if the function is declared as the following?

const virtual int getNumber();

What is the difference between those two?

Answer 1

As was already said, there is no difference. However, note that these two do differ:

virtual const int getNumber();
virtual       int getNumber() const;

In the first method, const refers to the returned value of type int.

In the second method, const refers to the object the method is called on; that is, this will have type T const * inside this method, - you will be able to call only const methods, modify only mutable fields and so on.

Answer 2

There's no difference. A declaration's specifiers can usually be written in any order.

Answer 3

There is no difference. If we look at the grammar summary for a decl-specifier-seq we can see that it's defined in a recursive manner:

decl-specifier:
     type-specifier

decl-specifier-seq:
     decl-specifier decl-specifier-seq

The only restriction is that const and volatile can be combined with any type specifier except themselves (no const const, volatile volatile, etc), there is no rule on the order in which you use them.

Answer 4

No difference. You can apply modifiers in your favourite order.