struct

1. Create simple struct
2. Change attributes of a mutable struct
3. Implement a method for a struct
4. Struct method to modify fields
5. Struct inheritance
6. Struct composition: Circle
7. Struct composition: Line
8. Struct with vector of structs - Polygon
9. Printing struct fails
10. Print struct - implement Display
11. Debug struct - implement Debug
12. Derive Debug for struct
13. Struct with vector and optional value
14. Printing and debug-printing simple struct
15. Use a tuple as a struct to represent color
16. Add method to tuple-based struct
17. Struct with method
18. Structs and circural references
19. new method with default values for struct
20. The new method has no special feature
21. Default values
22. Empty string and zero as default values
23. Derived Default values
24. Default for composite struct
25. Compare structs for Equality
26. Compare structs for Equality - manual implementation
27. Compare structs for partial equality - PartialEq
28. Compare structs for ordering (sorting) - Ord
29. Compare structs for partial ordering (sorting) - PartialOrd
30. Manually implement ordering
31. Copy attributes from struct instance
32. Drop - destructor
33. Exercise - struct for contact info
34. Solution - struct for contact info
35. Read from a file and return a struct
36. Converting between types: The From and Into traits
37. From and Into for String and &str
38. Implementing the From trait for 2D and 3D point structs