Use of 'const' for function parameters

Question

How far do you go with const? Do you just make functions const when necessary or do you go the whole hog and use it everywhere? For example, imag

Answer 1

Const parameter is useful only when the parameter is passed by reference i.e., either reference or pointer. When compiler sees a const parameter, it make sure that the variable used in the parameter is not modified within the body of the function. Why would anyone want to make a by-value parameter as constant? :-)