Upgrade to Pro — share decks privately, control downloads, hide ads and more …

Protocols All The Way Down - dotSwift, Paris, January 2018

Protocols All The Way Down - dotSwift, Paris, January 2018

A talk about the benefits and drawbacks of Protocol Oriented Programming, and protocols with default implementations.

Video:
https://www.dotconferences.com/2018/01/ellen-shapiro-protocols-all-the-way-down

Playground:
https://github.com/designatednerd/ProtocolPlayground

Ellen Shapiro
PRO

January 29, 2018
Tweet

More Decks by Ellen Shapiro

Other Decks in Technology

Transcript

  1. PROTOCOLS
    ALL THE WAY DOWN
    DOT SWIFT | PARIS, FRANCE | JANUARY 2018
    @DESIGNATEDNERD | BAKKENBAECK.COM | JUSTHUM.COM

    View Slide

  2. View Slide

  3. PROTOCOL-ORIENTED
    PROGRAMMING

    View Slide

  4. View Slide

  5. View Slide

  6. PROTOCOL-ORIENTED
    PROGRAMMING

    View Slide

  7. PROTOCOLS WITH
    DEFAULT IMPLEMENTATIONS

    View Slide

  8. View Slide

  9. View Slide

  10. View Slide

  11. View Slide

  12. DEFAULT PROTOCOL IMPLEMENTATION
    extension

    View Slide

  13. View Slide

  14. View Slide

  15. View Slide

  16. View Slide

  17. View Slide

  18. View Slide

  19. View Slide

  20. View Slide

  21. View Slide

  22. View Slide

  23. View Slide

  24. View Slide

  25. View Slide

  26. CONDITIONAL
    DEFAULT PROTOCOL IMPLEMENTATION
    extension

    View Slide

  27. View Slide

  28. View Slide

  29. View Slide

  30. View Slide

  31. extension

    View Slide

  32. View Slide

  33. View Slide

  34. View Slide

  35. View Slide

  36. where Self:...

    View Slide

  37. View Slide

  38. View Slide

  39. github.com/designatednerd/
    ProtocolPlayground

    View Slide

  40. View Slide

  41. View Slide

  42. View Slide

  43. View Slide

  44. View Slide

  45. View Slide

  46. MULTIPLE
    where CLAUSES

    View Slide

  47. View Slide

  48. View Slide

  49. View Slide

  50. View Slide

  51. View Slide

  52. View Slide

  53. View Slide

  54. View Slide

  55. View Slide

  56. View Slide

  57. View Slide

  58. View Slide

  59. SUBCLASS-LIKE BEHAVIOR
    WITHOUT
    THE BAGGAGE OF SUBCLASSING

    View Slide

  60. CENTRALIZATION!
    DRY CODE!

    View Slide

  61. NO INSANE
    INHERITANCE TREES

    View Slide

  62. PROTOCOL-ORIENTED
    ! PITFALLS

    View Slide

  63. POP QUIZ

    View Slide

  64. View Slide

  65. View Slide

  66. View Slide

  67. View Slide

  68. View Slide

  69. View Slide

  70. View Slide

  71. View Slide

  72. TYPE INFERENCE: !

    View Slide

  73. TYPE INFERENCE: !

    View Slide

  74. TYPE INFERENCE: !

    View Slide

  75. SPECIFYING PROTOCOL TYPE: !

    View Slide

  76. SPECIFYING PROTOCOL TYPE: !

    View Slide

  77. SPECIFYING PROTOCOL TYPE: !

    View Slide

  78. SPECIFYING PROTOCOL TYPE: !

    View Slide

  79. SPECIFYING PROTOCOL TYPE: !

    View Slide

  80. View Slide

  81. View Slide

  82. View Slide

  83. DEFAULT IMPLEMENTATIONS
    VS.
    EXTENSIONS
    VS.
    SUBCLASSES

    View Slide

  84. DEFAULT IMPLEMENTATIONS
    **(PLAIN VANILLA OR CONDITIONAL)
    VS.
    EXTENSIONS
    VS.
    SUBCLASSES

    View Slide

  85. > Do I need this to work on all instances and/or
    subclasses of a particular thing?
    Extension!
    > Do I need this method to work only when I say it should,
    or in a particular combination of circumstances?
    Default implementation!
    > Does this always need to be called from a particular
    lifecycle or delegate method?
    Subclass!

    View Slide

  86. CHOOSE YOUR TOOLS
    WISELY

    View Slide

  87. View Slide

  88. ! MERÇI BEAUCOUP! !

    View Slide

  89. LINKS!
    > Protocol-Oriented Programming, WWDC 2015
    developer.apple.com/videos/play/wwdc2015/408
    > The ghost of Swift Bugs Future, Alexandros Salazar
    nomothetis.svbtle.com/the-ghost-of-swift-bugs-
    future

    View Slide

  90. PHOTO CREDITS!
    > Businessman, by Daniel X. O'Neil
    flickr.com/photos/juggernautco/6037175371
    > Hammered Screw, by Justin Baeder
    flickr.com/photos/justinbaeder/5317820857
    > Knot, by JP Davidson
    flickr.com/photos/jpdavidsonimages/4677642617

    View Slide