Logical program organization

Lecture 3 - Slide 22 : 27

Logical program organization

Namespaces are used for the logical program organization of C++ programs

The C++ Prog. Lang. (3. edition): Page 167, 847

The C++ Prog. Lang. (4. edition): Page 54, 391

Namespaces
- A namespace is a named scope
- Use of names requires namespace qualification, with use of the scope resolution operator ::
  - namespace::name_within_namespace
- A using declaration can be used to add a name (an alias) to a local scope (such as a function) from a namespace
  - using N::name;
  - name is declared/defined as a local synonym to N::name
- A using directive allows convenient access to names from a given namespace
  - using namespace N;
  - Can - and should - be used locally, in a function for instance

Classes and structs

Illustration of using declarations and using directives - by example.

Compilable variant of the program from above.

Names declared in a namespace - natively or by using declarations - take priority over names brought in via using directives