Wishful Thinking - Code Review With Myself

Workshop presented at Ruby Fun Day 2014

Transcript

1. @NicolasPapagna nicolas.papagna@10pines.com Work @ TA @ Facultad de Ciencias Exactas y Naturales (UBA)
2. Thinking Wishful Review
3. We ain't nothing like frogs... … or are we?
4. Foolin’ ourselves
5. Whenever we’re looking out into the world, we’re always seeing ourselves, we’re not really seeing what’s out there. We have to learn very carefully how to see what’s out there.
6. shape the way we THINK Team Culture and Programming Languages
7. object oriented programming
8. Collaborating through messages We only have objects
9. Let’s talk about oop
10. Let’s talk about oop a Customer a Catalog
11. PROGRAM A simulation of the real world
12. LEARN To build a program we EXPRESS and knowledge
13. OBJECT = CODE + DATA True or false?
14. OBJECT A representation of something from the real world
15. Let’s talk about oop How can we tell how good our models are?
16. Let’s talk about oop
17. stuff.deposit stuff.withdraw stuff.balance Let’s talk about oop Name That Stuff
18. stuff.to_json stuff.save! stuff.balance Let’s talk about oop Name That Stuff!
19. Let’s talk about oop
20. MESSAGES The essence of something from the real world is determined by the the object respond to
21. Let’s model a traffic light
22. Let’s model a traffic… light?
23. Let’s model dance!
24. if movie.title == ‘The Godfather’ Let’s talk about oop
25. if movie.is_titled? ‘The Godfather’ Let’s talk about oop
26. DON’T BREAK ENCAPSULATION Trust your objects
27. SEMANTICS Two objects are polymorphic regarding a SET OF MESSAGES when they respond them with the same
28. ITS ALL ABOUT MESSAGES Polymorphism does not depend on classes*
29. ORGANIZE KNOWLEDGE we acquire from the real world We use Classes to
30. Say what? Code s/b expressive enough. Only Hacks / WTFs / Black Magic Let’s talk about oop All the way. Getters & Setters Included. You name it! Non trivial stuff. Comments first, then code. How much should we comment?
31. The motivation that drives the creation of a subclass should be Let’s talk about oop ESSENTIAL to the parent’s class domain
32. CRITERIA We should follow the same when adding subclasses at each inheritance level
33. Let’s talk about oop Document Encrypted Document Compressed Document Encrypted-Compressed Document Compressed-Encrypted Document
34. What is an abstract class? How do they relate? What is a concrete class? Let’s talk about oop
35. Let’s talk about oop
36. If we add an instance variable to an abstract class: Does it make it concrete? Let’s talk about oop
37. Test driven development
38. TAKE NOTES about the things we learn from the real world TDD is the way we
39. INDIVIDUAL EXAMPLE about a thing we learn from the real world Each test represents an
40. let's talk about tdd TDD leads to good designs. True or false? False. TDD leads to testable designs.
41. let's talk about tdd It is OK to write all test before coding. True or false? False. Why?
42. let's talk about tdd Is TDD the same as Unit Testing? By the way, what is a "unit"?
43. design patterns
44. let's talk about design patterns (Burger + Cheese + Bread) Decorators can be used to represent better the real world True or false? Not always. They model cross-cutting concerns.
46. let's talk about design patterns Should null objects inherit from our models? Is that “right”?
47. summary Be critic about things you take for granted (OOP). Constantly remind yourself that the culture we live in shapes the way we think (TDD). Code using a programming language. Don’t let it “code” you (Design Patterns).
48. Questions?
49. You Thank @10pines @NicolasPapagna development@10pines.com nicolas.papagna@10pines.com
50. references Alan Kay - Normal Considered Harmful https://www.youtube.com/watch?v=FvmTSpJU-Xc Alan Kay – The Early History of Smalltalk https://github.com/worrydream/EarlyHistoryOfSmalltalk Fred Brooks - No Silver Bullet http://faculty.salisbury.edu/~xswang/Research/Papers/SERelated/no-silver-bullet.pdf Wishful Thinking http://en.wikipedia.org/wiki/Wishful_thinking Betty Edwards – Drawing On The Right Side Of The Brain http://www.amazon.com/Drawing-Right-Side-Brain-Definitive/dp/1585429201 Kent Beck - TDD By Example http://www.amazon.com/Test-Driven-Development-By-Example/dp/0321146530 Alan Kay – The Computer Revolution Hasn’t Happened Yet https://www.youtube.com/watch?v=oKg1hTOQXoY