Question

I am reading some C++ text from the address https://cs.senecac.on.ca/~chris.szalwinski/archives/btp200.081/content/overl.html.
in the first lines, they say:

The signature of a member function consists of:

• the function name,

• the data types of its parameters,

• the order of the parameters and
  possibly

• the const status of the function.

I don’t understand what they mean by saying “the const status of the function“.

Can anyone elaborate on that, please?
Thanks.

Answer 1

In C++, you can declare a member function of a class to be const, by appending that keyword to its signature (for instance, int MyClass:doSomething(int param) const {...}). Doing so guarantees that the function won’t change the (non-mutable) members of the class object on which the function is called – and hence it can be called with const instances of that class.

It is permissible to have two different member functions for a class whose signature differs only in whether they are declared const or not.