Enum

1. Why enums
2. Enum to represent exit status
3. Enum to represent exit code
4. Enumeration of the 7 days of the week
5. Enumeration with non-exhaustive patterns
6. Enumeration and manual comparision
7. Enumeration and order
8. Enumeration colors - functions and String
9. Enumeration colors - functions and str
10. Enumeration colors - with method
11. Enumeration colors - with constructor
12. Enumerate without PartialEq using match
13. Struct using enum
14. Exercise: enum for programming languages
15. Solution: enum for programming languages
16. The Result enum