How to Write Pleasant Code

[RubyConf 2019 - Roman Kofman]

As we grow from beginner to intermediate developers, we tend to learn tools and Best Practices for writing good code. But. The more we learn, the more contradictions show up -- and the murkier it gets to find the right answers. Senior developers sometimes chime in with "it depends!". Which -- while being technically accurate, is also completely unhelpful. What does it depend on? How do we reconcile Best Practices when they conflict with each other? Who is "good" code actually good for? Is perfectly clean code even possible?

We'll learn to find the answers to all of these questions by exploring the discipline of Design (think fancy chairs in museum); and stealing from it shamelessly.

Transcript

1. https://jake-ketchum.squarespace.com/blog/2017/4/20/metal-working-deconstruction-hammer ROMAN KOFMAN - @RKOFMAN How to write pleasant code
2. https://www.flickr.com/photos/matthewbraid/2298403782 @rkofman
3. https://www.flickr.com/photos/philipandlab/10685836895 @rkofman
4. The code we write is itself a tool for producing future software. @rkofman
5. For me the purpose of life is partly to have joy. … So Ruby is designed to make programmers happy. Yukihiro Matsumoto @rkofman
6. How do we make code a better tool? @rkofman
7. @rkofman
8. https://refactoring.com/ @rkofman
9. https://refactoring.com/ @rkofman
10. @rkofman
11. Presentation Title PRESENTER’S NAME https://www.flickr.com/photos/brighton/6878091316 @rkofman
12. Code Design Principles • DRY - Don’t repeat yourself • High Cohesion / Low Coupling • SOLID @rkofman
13. Code Design Principles • DRY - Don’t repeat yourself • High Cohesion / Low Coupling • SOLID • Single Responsibility • Open / Closed • Liskov Substitution • Interface Segregation • Dependency Inversion @rkofman
14. @rkofman
15. Code Design Principles • YAGNI - Ya aren’t gonna need it • Wrong Abstraction vs Duplication • Composition over Inheritance @rkofman
16. get '/employee/:id' do |id| employee = Employee.find id EmployeePresenter.new(employee).serialize end @rkofman
17. get '/employee/:id' do |id| employee = Employee.find id EmployeePresenter.new(employee).serialize end get '/employees' do employees = Employee.find_all employees.map do |employee| EmployeePresenter.new(employee).serialize end.to_s end @rkofman
18. class EmployeePresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.family_name}" end end @rkofman
19. Feature: Add job title to employee page @rkofman
20. get '/employee/:id' do |id| employee = Employee.find id EmployeePresenter.new(employee).serialize end @rkofman
21. class EmployeePresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.family_name}" end end @rkofman
22. class EmployeePresenter def initialize employee @e = employee @job = Job.find employee.job_id end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary}, job: #{@job.title} \}} end def full_name "#{@e.given_name} #{@e.family_name}" end end @rkofman
23. get '/employee/:id' do |id| employee = Employee.find id EmployeePresenter.serialize employee end get '/employees' do employees = Employee.find_all employees.map do |employee| EmployeePresenter.serialize employee end.to_s end @rkofman
24. get '/employees' do employees = Employee.find_all employees.map do |employee| EmployeePresenter.serialize employee end.to_s end @rkofman
25. employees.map do |employee| EmployeePresenter.serialize employee end.to_s @rkofman
26. Fail! @rkofman
27. class EmployeePresenter def initialize employee @e = employee @job = Job.find employee.job_id end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary}, job: #{@job.title} \}} end def full_name "#{@e.given_name} #{@e.family_name}" end end @rkofman
28. class EmployeePresenter def initialize employee, job @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary}, job: #{@job.title} \}} end def full_name "#{@e.given_name} #{@e.family_name}" end end @rkofman
29. Presentation Title PRESENTER’S NAME https://www.flickr.com/photos/jerthebear/5850272087/ @rkofman
30. class EmployeePresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.f... end end class EmployeePresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.fam end end @rkofman
31. class EmployeePresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.f... end end class EmployeeListPresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.fam end end @rkofman
32. @rkofman
33. https://www.flickr.com/photos/librariesrock/14796401088/ @rkofman
34. def fibonacci n if n == 1 || n == 2 1 else fibonacci(n-1) + fibonacci(n-2) end end def fibonacci n second_last = 1 (1..n-2).inject(1) do |last, i| current = second_last + last second_last = last current end end Which is better? @rkofman
35. Which is better? https://www.flickr.com/photos/aikos/9431411118 https://www.flickr.com/photos/cogdog/30819427850 @rkofman
36. https://www.flickr.com/photos/foilman/26792892279 @rkofman
37. We need to focus on humans, on how humans care about doing programming. — Matz @rkofman
38. Design https://commons.wikimedia.org/wiki/File:Centre_norv%C3%A9gien_de_design_et_darchitecture_(DOGA)_(4852913778).jpg @rkofman
39. Human Centered Design @rkofman
40. Presentation Title PRESENTER’S NAME https://www.flickr.com/photos/jeanbaptisteparis/5863913142 @rkofman
41. @rkofman
42. Person Action Context @rkofman
43. Person https://www.flickr.com/photos/wocintechchat/25388752744 @rkofman
44. Person • Be very specific; make them real • Explore edge-cases @rkofman
45. Context https://www.flickr.com/photos/stevensnodgrass/30950768880 @rkofman
46. Context Story time! @rkofman
47. Context • Knowledge • Intention • Social environment @rkofman
48. Action @rkofman
49. Action • Perception • Action • Feedback @rkofman
50. Person Action Context Human Centered Design @rkofman
51. class EmployeePresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.f... end end class EmployeePresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.fam end end @rkofman
52. class EmployeePresenter def initialize employee @e = employee end def serialize employee %{\{ full_name: #{full_name}, salary: #{@e.salary} \}} end def full_name "#{@e.given_name} #{@e.family_name}" end end @rkofman
53. get '/employees' do employees = Employee.find_all employees.map do |employee| EmployeePresenter.new(employee).serialize end.to_s end @rkofman
54. get '/employees' do employees = Employee.find_all without_db do # throws errors if DB queries are attempted employees.map do |employee| EmployeePresenter.new(employee).serialize end.to_s end end @rkofman
55. Inspiration + Research Code Quality • Sarah Mei — Livable Code (RailsConf 2018) • Joe Mastey — Bringing UX to Your Code (RailsConf 2015) • Sandi Metz — Practical Object-Oriented Design in Ruby • Martin Fowler — Refactoring • Jim Weirich - Connascence Examined @rkofman
56. Inspiration + Research Design • Steve Krug — Don’t Make Me Think • Robin Williams — Non-Designer’s Design Book • Don Norman — Design of Everyday Things • Webitects — (Where I first learned about Design + Contextual Research) @rkofman
57. https://jake-ketchum.squarespace.com/blog/2017/4/20/metal-working-deconstruction-hammer How to write pleasant code ROMAN KOFMAN - @RKOFMAN
58. square.com How to write pleasant code ROMAN KOFMAN - @RKOFMAN