Less Abstract! Surprising effects of expressing OOP in pictures

Transcript

1. Less Abstract! Effects of expressing OOP in pictures Ivan Nemytchenko

   @inemation inem.at

2. Who is this guy? • Educator • Freelance consultant •

   Complexity fighter • GitLab fan • Serbian Siberian • inem.at • @inemation

3. Serbian Siberian ??

4. I am Russian

5. None
6. None

7. Omsk is in Siberia

8. I live in Serbia

9. Serbia != Siberia

10. Serbia != Siberia != Syria

11. What’s the problem? Abstractions on top of abstractions on top

    of other abstractions!

12. What’s the problem? Very hard to see the big picture

    in real projects

13. What’s the problem? Very hard to see the big picture

    in real projects CRC Cards

14. What’s the problem? Very hard to see the big picture

    in real projects UML :(

15. What to expect here? 1. It is gonna be fun!

    2. You’ll become better at: • Learning, teaching, explaining complex concepts • Visualizing big picture • Finding architecture flaws •Tracking dynamics

16. OOP in pictures Foundation Advanced concepts Using in practice

17. How to illustrate Dependency Injection * with one picture **

    so that everyone understands ?

18. “Smart kettle” task Boil water correctly and safely! 1. No

    code 2. Just classes 3. And their methods

19. Artistic soldiers method

20. Kettle components (objects) small dudes == objects

21. Kettle components (objects) small dudes == objects

22. Kettle components (objects) small dudes == objects

23. Kettle components (objects) small dudes == objects

24. Objects with methods! arms == methods

25. A method number of fingers == number of arguments

26. Instance variables Stored inside the brain

27. Instance variables Can be reused later

28. But how other stuff is going to look like?…

29. Returning results door on the body

30. Private methods “internal arms”

31. Exception puking

32. Basic anti-patterns

33. Too many arguments

34. Too many methods

35. Too long methods

36. Too many instance variables

37. Too much conditional logic in methods Swallen arms

38. Too much of everything!!!

39. OOP in pictures Foundation Advanced concepts Using in practice

40. Polymorphism same number of hands with same number of fingers

41. None
42. None

43. Classes A spawning platforms

44. Classes A spawning platform

45. same topology Object & classes have the

46. Topology Cups and donuts share the same topology

47. same topology Object & classes have the

48. Execution flow

49. Execution flow

50. Execution flow

51. Execution flow == Rube Goldberg machine

52. Execution flow

53. Execution flow

54. Execution flow

55. Dependencies have to remember about classes to use them

56. Dependencies

57. Side effects

58. Dependency Injection Instead of remembering thing we pass them as

    arguments
59. None

60. OOP in pictures Foundation Advanced concepts Using in practice

61. Visual language!

62. None
63. None
64. None
65. None
66. None
67. None
68. None
69. None
70. None
71. None
72. None

73. Big picture

74. Dynamic anti-patterns

75. Dynamic anti-patterns

76. Dynamic anti-patterns

77. Dynamic anti-patterns

78. Dynamic anti-patterns

79. None
80. None
81. None
82. None
83. None
84. None
85. None

86. OOP in pictures Foundation Advanced concepts Using in practice

87. None

88. – George Box “All models are wrong but some are

    useful.”

89. • Big picture • Modelling • Documenting • Sharing knowledge

    • Explaining What can you use it for

90. Ivan Nemytchenko, inem.at, @inemation RubyConf 2019 Questions?