Constants

Lecture 2 - Slide 28 : 29

Constants

The const qualifier can be used in several different contexts in C++

Constness is a fairly complicated matter in C++

The basics
- The const qualifier can be applied to objects, types, and member functions
- Constant objects cannot be mutated
Pointers and const
- Either a constant pointer or a pointer to something constant
  - this is a constant pointer
- *const is declarator operator - constant pointer
  - Other declarator operators: *, [], and ()

References and const
- By nature a reference is constant - once the reference is establised it cannot be changed
Member functions and const
- A constant member function cannot modify the state of the object

Examles constants, pointers to constants, and constant pointers.

Only the valid parts of the program from above - compiles.

point.h - just for reference.

point.cc - just for reference.