ICYMI: Enums Are... by Jessie Linden

2 facts about me: I am obsessed with enums, and I am a professional drummer and percussionist 🎵

For this talk, I'd like to marry these great loves by

1. sharing my curiosity about enums with the SwiftLeeds community
2. leveraging my musical skills as the backdrop for a sample app called PocketPerc: Beat Generator

In the app, a user would be able to toggle on any number of instrument samples to build a unique groove all their own, with samples largely recorded by me 🥁

To build up to the beat part (obviously the Grand Finale), I’d like to showcase enums in all their glory, aka possibly/hopefully using them way too much and inspiring some wild ideas about what they can do 🤗 The static data we would need is a perfect opportunity to eclipse structs and classes as the go-to data types, and instead rely heavily on enums to build views and stay categorized! To make it extra fun, I plan to limit myself as much as possible to only that data type, see what boundaries we bump up against, and discuss where and why we might want to pivot to another structure for production.

Here’s a non-exhaustive list of the power moves I’ve been exploring:

Protocol conformance CaseIterable, Equatable and Comparable conformances Associated values (with and without default values) Pattern matching Screen management Static properties Computed properties Interaction with ObservableObjects Custom raw types

Recorded at SwiftLeeds: https://www.youtube.com/watch?v=EANs31LTH6A

Transcript

1. Jessie Linden | she/her ICYMI: Enums Are The Sh*t Swift Leeds 2023
2. Why enums?
3. John Sundell “Depending on who you ask, enums are either , or in Swift.” under-utilized over-used
4. under-utilized over-used
5. PocketPerc
6. PocketPerc 1 2 3 4 fill
7. Horns Fill RepeatMode PlaybackControls Rhythm Track Mallets Latin Category SheetState SortStyle PlaybackState Mix SoloMode TrackControls SheetType TimeConstant ViewState SelectionState 20
8. PocketPerc • app demo • code • make a mix
10. The Basics
11. The Basics category finite list of options
12. The Basics
13. Raw Type The Basics
14. Associated Values Raw Type with The Basics
15. Associated Values The Basics
16. Associated Values The Basics
17. Associated Values The Basics
18. Associated Values The Basics
19. Associated Values The Basics
20. surprise fill! The Basics
21. The Basics
22. Pattern Matching With Associated Values The Basics
23. The Basics Pattern Matching With Associated Values
24. The Basics Pattern Matching With Associated Values
25. The Basics Pattern Matching With Associated Values
26. Protocol Conformance The Basics
27. Nested structures The Basics
28. Nested structures Custom initializers The Basics
29. Nested structures Custom initializers Functions The Basics
30. Nested structures Custom initializers Functions Mutating functions The Basics
31. Nested structures Custom initializers Functions Mutating functions Static functions The Basics
32. Nested structures Custom initializers Functions Mutating functions Static functions Static properties The Basics
33. Nested structures Custom initializers Functions Mutating functions Static functions Static properties Computed properties The Basics
34. Nested structures Custom initializers Functions Mutating functions Static functions Static properties Computed properties
35. Nested structures Custom initializers Functions Mutating functions Static functions Static properties Computed properties
36. Enums can’t contain stored properties.
37. Enums can’t contain stored properties. Enums can’t hold state.
39. Representing State
40. Representing State
41. Representing A Collection
42. Representing A Collection
43. Representing A Collection
44. Representing A Collection
45. Using Enums to Increase Coherence
46. 0 & 1 Using Enums to Increase Coherence : Boolean isEmpty var
47. 0 & 1 : true & false Boolean Using Enums to Increase Coherence isEmpty var
48. two-cased enum Boolean Using Enums to Increase Coherence
49. Add additional cases later Switch statement protection More readable two-cased enum benefits Using Enums to Increase Coherence
50. Representing A Collection
51. Representing A Collection
52. Representing A Collection
53. Using Enums to Increase Coherence Part 2
54. Using Enums to Increase Coherence Part 2
55. Using Enums to Increase Coherence
56. Using Enums to Increase Coherence
57. Using Enums to Increase Coherence
58. Using Enums to Increase Coherence
59. Using Enums to Increase Coherence
60. Using Enums to Increase Coherence
61. Using Enums to Increase Coherence
62. Using Enums to Increase Coherence
63. Using Enums to Increase Coherence
65. CaseIterable Bonus
66. CaseIterable Bonus
67. Streamlining Multiple States
68. Streamlining Multiple States i.e. mitigating single source of truth violations
69. Streamlining Multiple States
70. Streamlining Multiple States ! Multiple Conditional Checks…
71. ! Multiple Conditional Checks… …Can Mean Multiple States ! Streamlining Multiple States
72. Streamlining Multiple States
73. Streamlining Multiple States isPlaying currentTime disabled default false true 0
74. Streamlining Multiple States false true 0 false true ??:?? isPlaying currentTime disabled default
75. Streamlining Multiple States false true 0 false true ??:?? isPlaying currentTime disabled default false false 5:24… or whatever
76. Streamlining Multiple States false true 0 false true ??:?? isPlaying currentTime disabled default false false 5:24… or whatever
77. Streamlining Multiple States ! Multiple Conditional Checks !
78. Streamlining Multiple States
79. Streamlining Multiple States
80. Streamlining Multiple States
81. Streamlining Multiple States
82. 30 Streamlining Multiple States
83. Streamlining Multiple States
84. AVAudioPlayerNode AVAudioPlayer? PlaybackState Bonus!
85. AVAudioPlayerNode AVAudioPlayer? PlaybackState Bonus!
86. PlaybackState Bonus!
87. ICYMI: Enums Are The Sh*t
88. The nugget that started it all…
89. TrackView solo pan volume mute
90. TrackView solo pan volume mute
91. TrackView solo pan volume mute
92. TrackView solo pan volume mute Enums That Conform To View!!!!!
93. Enums That Conform To View!!!!!
94. Enums That Conform To View!!!!! v
95. Enums That Conform To View!!!!!
96. Enums That Conform To View!!!!!
97. Enums That Conform To View!!!!!
98. Enums That Conform To View!!!!!
99. Why enums?
100. Why enums? Enums. Are. The. Sh*t.
101. Questions? code deck resources Github