[RubyKaigi 2024] Ruby Mixology 101: adding shots of PHP, Elixir, and more

https://rubykaigi.org/2024/presentations/palkan_tula.html

How often have you heard, “I wish Ruby had X from Y”? Developers tend to desire features they love in one language to be available in another. That’s why, for example, we got pattern matching and shorthand Hashes added to Ruby. What’s next? What will inspire the next Ruby syntax addition? Crystal? Elixir? Zig (have you heard about it)? PHP (why not)?

Let’s embark on a fantastic journey of exploring syntax features from other languages, such as method overloading or null coalescing assignment, and how to port them to Ruby. But why is it fantastic? I want to turn fantasy into reality and show how we can experiment with Ruby syntax additions without waiting for official releases with experimental features.

Transcript

2. palkan_tula palkan Why is Ruby impressive? 2 ͳͥRuby͸͍͢͝ͷ͔
5. palkan_tula palkan h = {x:, y:} def foo(&) bar(&) 5 2015 2018 2019 2020 2021 2022 2024 1... &. ...1 case ... in def x = 1 def foo(*) bar(*) 1 in x proc { it } def foo(...) proc { _1 }
6. palkan_tula palkan 6 2024 2025 2026 2027 2028 2029 2030 proc { it } ?? ?? ?? ?? ?? ??
7. palkan_tula palkan –D. Crystal “The only languages which do not change are dead ones” 7 มΘΒͳ͍ݴޠ͸ࢮΜͩݴޠͰ͢ɻ
8. palkan_tula palkan 8 2024 2025 2026 2027 2028 2029 2030 proc { it } ?? ?? ?? ?? ?? ??
9. palkan_tula palkan 8 2024 2025 2026 2027 2028 2029 2030 proc { it } ?? ??
10. palkan_tula palkan 15 2013 2015 2017 2019 2020 2021 &. proc { it } 2024 proc { it } &. h = {x:, y:} case ... in case ... in h = {x:, y:} def x = 1 def x = 1
11. palkan_tula palkan Adding new syntax is irreversible 16 ৽͍͠จ๏Λಋೖ͢Δͱޙ໭ΓͰ͖ͳ͍
12. palkan_tula palkan How to predict new syntax benefits? 17 ৽͍͠จ๏ͷϝϦοτΛͲ͏༧ଌ͢Δ͔
13. palkan_tula palkan I. Encourage early adopters to experiment with proposals. 18 ΞʔϦʔΞμϓλʔʹ৽نఏҊͰ࣮ݧͯ͠΋Β͏
14. palkan_tula palkan 19
20. RubyKaigi
21. RubyWasmKaigi
22. 28 github.com/palkan
23. 29 evilmartians.com
24. 30 urlgeni.us/amazon/Rails-book
25. LET'S START MIXING ʮ࢝ΊΑ͏ʂʯ
26. palkan_tula palkan I. Encourage early adopters to experiment with proposals. 32 ΞʔϦʔΞμϓλʔʹ৽نఏҊͰ࣮ݧͯ͠΋Β͏
27. palkan_tula palkan I. Encourage early adopters to experiment with proposals. II. Learn from other languages. 32 ΞʔϦʔΞμϓλʔʹ৽نఏҊͰ࣮ݧͯ͠΋Β͏ ଞͷݴޠΛࢀߟʹ͢Δ
28. palkan_tula palkan h = {x:, y:} 33
29. palkan_tula palkan h = {x:, y:} 33
30. palkan_tula palkan h = {x:, y:} 33
31. palkan_tula palkan 1
34. palkan_tula palkan user["name"] = user["name"] ?: "Guest" 36 PHP: $user['name'] ??= 'Guest' Kotlin: JavaScript: user.name ??= 'guest' Elvis operator
35. palkan_tula palkan 37
36. palkan_tula palkan ! → " SyntaxError Use cases Implementation 38 ࣮૷ Ϣʔεέʔε
37. palkan_tula palkan ?= 39
38. palkan_tula palkan $ 40 ruby -e 'a ?= 1' -e:1: syntax error, unexpected integer literal, expecting end-of-input a ?= 1 -e: compile error (SyntaxError)
39. palkan_tula palkan ?= a = nil a ?= false # a is false a ?= 1 # a is false a ||= 1 # a is 1 41
41. palkan_tula palkan Use cases I. (a = false) ?= 2024 #=> false ... 43 Ϣʔεέʔε
42. palkan_tula palkan 44
43. palkan_tula palkan 45
45. palkan_tula palkan ?= ❤ Hash h = {val: nil} # h[:val] = 42 unless h.key?(:val) h[:val] ?= 42 h #=> {val: nil} 47
46. palkan_tula palkan ?= ❤ @var def current_user return @current_user if defined?(@current_user) @current_user = find_user end 48
47. palkan_tula palkan def current_user @current_user ?= find_user end 49 def current_user return @current_user if defined?(@current_user) @current_user = find_user end ?= ❤ @var
49. palkan_tula palkan def current_user @current_user ?= find_user end 51 def current_user return @current_user if defined?(@current_user) @current_user = find_user end ?= ❤ @var
50. palkan_tula palkan ΦϒδΣΫτγΣΠϓ def current_user @current_user ?= find_user end 51 def current_user return @current_user if defined?(@current_user) @current_user = find_user end $ Object shapes :( ?= ❤ @var
52. palkan_tula palkan I. (a = false) ?= 2024 #=> false 53 Use cases Ϣʔεέʔε
53. palkan_tula palkan I. (a = false) ?= 2024 #=> false II. h[:x] ?= 5 53 Use cases Ϣʔεέʔε
54. palkan_tula palkan I. (a = false) ?= 2024 #=> false II. h[:x] ?= 5 III. @value ?= maybe_some 53 Use cases Ϣʔεέʔε
55. palkan_tula palkan εϚʔτΦϒδΣΫτγΣΠϓ I. (a = false) ?= 2024 #=> false II. h[:x] ?= 5 III. @value ?= maybe_some ⏳ Smart object shapes 54 Use cases Ϣʔεέʔε
56. palkan_tula palkan ?= → ❤ SyntaxError Use cases Implementation 55 ࣮૷ Ϣʔεέʔε → lexer, parser
57. palkan_tula palkan 3
59. palkan_tula palkan def beach(*temperature) case temperature in :celcius | :c, (20..45) :favorable in :kelvin | :k, (293..318) :scientifically_favorable in :fahrenheit | :f, (68..113) :favorable_in_us else :avoid_beach end end 58
60. palkan_tula palkan beach(Temperature) -> case Temperature of {celsius, N} when N >= 20, N =< 45 -> 'favorable'; {kelvin, N} when N >= 293, N =< 318 -> 'scientifically favorable'; {fahrenheit, N} when N >= 68, N =< 113 -> 'favorable in the US'; _ -> 'avoid beach' end. 59
61. palkan_tula palkan beach({celsius, N}) when N >= 20, N =< 45 -> 'favorable'; beach({kelvin, N}) when N >= 293, N =< 318 -> 'scientifically favorable'; beach({fahrenheit, N}) when N >= 68, N =< 113 -> 'favorable in the US'; beach(_) -> 'avoid beach'. 60
62. palkan_tula palkan 61
63. palkan_tula palkan 62
64. palkan_tula palkan def beach(*temperature) case temperature in :celcius | :c, (20..45) :favorable in :kelvin | :k, (293..318) :scientifically_favorable in :fahrenheit | :f, (68..113) :favorable_in_us else :avoid_beach end end 63
65. palkan_tula palkan def beach in :celcius | :c, (20..45) :favorable end def beach in :kelvin | :k, (293..318) :scientifically_favorable end def beach in :fahrenheit | :f, (68..113) :favorable_in_us end def beach(...) = :avoid_beach 64
66. palkan_tula palkan $ 65 ruby -e 'def foo in :c, Integer => v; v; end' -e:1: syntax error, unexpected `in', expecting ';' or '\n' def foo in :c, Integer => v; v; end -e: compile error (SyntaxError)
67. palkan_tula palkan def ... in No new keywords Resembles other languages (Elixir, Crystal, etc.) Idiomatic Ruby & 66 ৽͍͠ΩʔϫʔυΛ૿΍͞ͳ͍ ଞͷݴޠʹࣅͤΔ Ruby ͷΠσΟΦϜʹै͏
70. palkan_tula palkan foo(*args) — ' 70
71. palkan_tula palkan foo(*args) — ' foo(**kwargs) — ' 70
72. palkan_tula palkan foo(*args) — ' foo(**kwargs) — ' foo(*args, **kwargs) — ( 70
73. palkan_tula palkan foo(*args) — ' foo(**kwargs) — ' foo(*args, **kwargs) — ( def foo in <ptrn> (if | unless) <expr> — ( 70
74. palkan_tula palkan foo(*args) — ' foo(**kwargs) — ' foo(*args, **kwargs) — ( def foo in <ptrn> (if | unless) <expr> — ( prepend/class_eval/etc. — ' 70
76. palkan_tula palkan How can we implement this? 72 ͲͷΑ͏ʹ࣮૷͢Ε͹ྑ͍͔ʁ
77. palkan_tula palkan 73 beach(Temperature) -> case Temperature of {celsius, N} when N >= 20, N =< 45 -> 'favorable'; {kelvin, N} when N >= 293, N =< 318 -> 'scientifically favorable'; {fahrenheit, N} when N >= 68, N =< 113 -> 'favorable in the US'; _ -> 'avoid beach' end. beach({celsius, N}) when N >= 20, N =< 45 -> 'favorable'; beach({kelvin, N}) when N >= 293, N =< 318 -> 'scientifically favorable'; beach({fahrenheit, N}) when N >= 68, N =< 113 -> 'favorable in the US'; beach(_) -> 'avoid beach'.
78. palkan_tula palkan ಉ͡όΠτίʔυ Same byte code 74 beach(Temperature) -> case Temperature of {celsius, N} when N >= 20, N =< 45 -> 'favorable'; {kelvin, N} when N >= 293, N =< 318 -> 'scientifically favorable'; {fahrenheit, N} when N >= 68, N =< 113 -> 'favorable in the US'; _ -> 'avoid beach' end. beach({celsius, N}) when N >= 20, N =< 45 -> 'favorable'; beach({kelvin, N}) when N >= 293, N =< 318 -> 'scientifically favorable'; beach({fahrenheit, N}) when N >= 68, N =< 113 -> 'favorable in the US'; beach(_) -> 'avoid beach'.
80. palkan_tula palkan SyntaxError Use cases Implementation 76 ࣮૷ Ϣʔεέʔε → parser def ... in → ❤
81. palkan_tula palkan 4
82. palkan_tula palkan def initialize(@a, @b) 78
83. palkan_tula palkan def initialize(@a, @b) 78
84. palkan_tula palkan CoffeeScript: define_method(:initialize) {|@a, @b|} 79 def initialize(@a, @b) initialize(@a, @b) -> def initialize(@name : String) Crystal: Ruby <1.9:
89. palkan_tula palkan SyntaxError Use cases Implementation 84 ࣮૷ Ϣʔεέʔε → parser, VM? def initialize(@a) → ❤
90. palkan_tula palkan Anonymous Struct 85
91. palkan_tula palkan Anonymous Struct 86
92. palkan_tula palkan ෆม Zig: 87 var pt: Point = .{ .x = 3, .y = 4, }; #{ x: 3, y: 4 } JavaScript (proposal): Anonymous Struct Immutable
93. palkan_tula palkan .{x: 3, y: 4} 88
95. palkan_tula palkan SyntaxError Use cases Implementation 90 ࣮૷ Ϣʔεέʔε → parser, stdlib .{x: 3, y: 4} → ❤
96. palkan_tula palkan 91
97. palkan_tula palkan 92
98. palkan_tula palkan |> 93
99. palkan_tula palkan ॓୊ |> 93 ) Your homework
100. palkan_tula palkan "https://api.github.com/repos/ruby/ruby" .then { URI.parse(it) } .then { Net::HTTP.get(it) } .then { JSON.parse(it).fetch("stargazers_count") } .then { "Ruby has #{it} stars" } .then { Kernel.puts(it) } 94
101. palkan_tula palkan "https://api.github.com/repos/ruby/ruby" |> URI.parse |> Net::HTTP.get |> JSON.parse(it).fetch("stargazers_count") |> "Ruby has #{it} stars" |> Kernel.puts 95
102. palkan_tula palkan Try using proposed syntax in your code Share you examples Report confusions and edge cases 96 ͜ͷจ๏Λࣗ෼ͷίʔυͰࢼͯ͠ΈΔ ॻ͍ͨίʔυΛڞ༗͢Δ ͏·͍͔͘ͳ͍ྫ΍ΤοδέʔεΛใࠂ
104. palkan_tula palkan 98 bit.ly/ruby-mixology
105. Thank You Slides: evilmartians.com/events Twitter: @palkan_tula, @evilmartians ͋Γ͕ͱ͏