Ruby.next

Slide-deck from my presentation at Grill.rb 2018 in Wroclaw, Poland.

Transcript

2. Hello!
3. Божидар
4. Bozhidar
5. Bozhidar
6. Bożydar
7. Bożydar
8. Bożo cool
9. @bbatsov
10. Sofia, Bulgaria Sofia, Bulgaria
15. bbatsov
16. Ruby, RSpec & Rails style guides
21. I’m back!
29. Not on Ruby’s Core Team
30. Matz on Ruby
31. Ruby is now mature
32. We’re aware of all of our mistakes
33. Compatibility is important
34. Most ideas for changes will be discarded
35. Ruby has survived for 24 years
37. Ruby is dead every year.
38. People are still making a living with Ruby
39. People are still making a living with COBOL
40. Build the things your users need, instead of the things they want.
42. The track record of recent Ruby innovation
43. Ruby != MRI
44. 3.times do puts "Ruby Rocks!" end
45. Ruby 2.0
46. •keyword arguments •%i •UTF-8 is now the default source file encoding •Refinements (experimental feature)
47. Ruby 2.1
48. •Rational/Complex Literal •defs return value •Refinements are no longer experimental feature
49. Ruby 2.2
50. Nada
51. Ruby 2.3
52. •frozen string literals pragma •safe navigation operator (&.) •squiggly heredocs (<<~)
53. Ruby 2.4
54. •Unify Fixnum and Bignum into Integer •Support Unicode case mappings
55. Ruby 2.5
56. •Top-level constant look-up is removed •rescue/else/ensure are allowed inside do/end blocks •refinements take place in string interpolations

58. Java innovates more!
59. JavaScript innovates way more!
61. Ruby.NEXT: Live Long and prosper by Bożydar Batsov
62. Ruby 2.6
63. •endless ranges (1..) •begin/else/end is now a syntax error (it used to be a warning) •some core lib methods now take optional keyword arguments (e.g. system(), Integer(), Float()) •a first stab at MJIT •built-in AST module
64. arr[1..-1]
65. arr[1..]
66. arr.drop(1)
67. There’s no easy way to express an infinite loop with index in Ruby
68. 1.step …
70. Float("foo", exception: false)
71. Float("foo", exception: false)
72. AST Module
73. pry(main)> Ripper.sexp('alias :some :test') => [:program, [[:alias, [:symbol_literal, [:symbol, [:@ident, "some", [1, 7]]]], [:symbol_literal, [:symbol, [:@ident, "test", [1, 13]]]]]]]
74. each(:method_add_arg, sexp) do |s| next if s[1][0] != :call receiver = s[1][1][1] method_name = s[1][3][1] if receiver && receiver[1] == 'Array' && method_name == 'new' && s[2] == [:arg_paren, nil] offences.delete(Offence.new(:convention, receiver[2].lineno, ERROR_MESSAGE)) add_offence(:convention, receiver[2].lineno, ERROR_MESSAGE) end end
75. What about Ruby 3.0?
76. Little is known about it…
77. Little concrete is known about it…
78. –Matz “We’ll aim to release Ruby 3 for the Olympic Games in Tokyo in 2020.”
79. Duck inference?
80. Better support for concurrent & parallel programming
81. Guilds
82. GIL -> Global Interpreter Lock
83. GIL -> Guild Interpreter Lock
84. https://olivierlacan.com/posts/ concurrency-in-ruby-3-with-guilds/
85. 3 times faster performance?
86. (3 times faster performance than Ruby 2.0)
87. Ruby 2.5 is 154% faster than Ruby 2.0
88. Getting rid of some quirky features?
89. We’re not going to repeat the Python 3 mistakes! — Matz
90. And what about the Perl 6 mistakes? — Bożydar
91. I’ve got a “secret” for you…
92. There’s no real plan for Ruby 3
93. Ruby 3 is not a real release!
94. Ruby 3 is an idea!
95. –Zach Tellman There has been a consistent migratory pattern from Ruby to node.js to Go, Rust, and Elixir. At first, each community is defined by its potential. But as that potential is realized, the community begins to be defined by its compromises. That change is felt most keenly by the people who were there first, who remember what it was like when anything seemed possible. They feel fenced in and so they move on, in search of their golden city…”
98. Good artists copy; great artists steal. — Pablo Picasso
99. We looked for “inspiration” everywhere…
100. PHP
101. Visual Basic Script
102. Java
103. The Future of Java and the JDK Who’s in charge? https://www.youtube.com/watch?v=HpbchS5kmio
104. Stewardship: The Sobering Parts https://www.youtube.com/watch?v=2y5Pv4yN0b0
105. Maintainer vs Programmer
106. Long-term vs short-term
107. Foresight vs short-sightedness
108. Key take-aways
109. You need a clear strategy
110. You need a detailed game-plan (roadmap) for implementing your strategy
111. Additive changes, instead of destructive ones
112. It’s better to deprecate than to remove
113. Small increments
114. Guiding principles
115. Ruby Next, the language
116. Design principle #0
117. Continuous thoughtful innovation
118. Design principle #1
119. Continue to optimize for happiness
120. Add some useful new features
121. Make deprecating things easy
122. class Foo # <b>DEPRECATED:</b> Please use <tt>useful</tt> instead. def useless warn "[DEPRECATION] `useless` is deprecated. Please use `useful` instead." useful end def useful # ... end end
123. class MyFile extend Gem::Deprecate def no_more close end deprecate :no_more, :close, 2015, 5 def close # new logic here end end
124. Immutable data structures
125. vector
126. v = @[1, 2, 3]
127. immutable hash
128. m = @{one: 1, two: 2}
129. immutable set
130. s = @${1, 2, 3}
131. s = ${1, 2, 3}
132. arr1 - arr2
133. [1,2] - [1,2,3] => [] [1,2,9] - [1,2,3] => [9]
134. ${1,2} ^ ${1,2,3} => [3] ${1,2,9} ^ ${1,2,3} => [9,3]
135. .to_immutable
136. .to_mutable
137. .to_v
138. Pattern Matching
139. class Struct def deconstruct; [self] + values; end end A = Struct.new(:a, :b) case A[0, 1] in (A, 1, 1) :not_match in A(x, 1) # Syntactic sugar of above p x #=> 0 end
140. class Struct def deconstruct; [self] + values; end end A = Struct.new(:a, :b) match A[0, 1] in (A, 1, 1) :not_match in A(x, 1) # Syntactic sugar of above p x #=> 0 end
141. https://bugs.ruby-lang.org/ issues/14912
143. Design principle #2
144. Simplicity
145. Simplicity is the ultimate sophistication.
146. Less is more
147. Simplicity leads to happiness.
148. Let’s deprecate some stuff
149. deprecate != remove
150. Let’s deprecate some useless stuff
151. for loops
152. for name in names puts name end
153. names.each do |name| puts name end
154. autoload
155. flip-flops
156. DATA.each_line do |line| print(line) if (line =~ /begin/)..(line =~ /end/) end
157. block comments
158. =begin comment line another comment line =end
159. Must be placed at the very beginning of a line
160. class SomeClass =begin This is a top comment. Or is it? =end def some_method end end
161. class SomeClass =begin This is a top comment. Or is it? =end def some_method end end
162. Character literals
163. pry(main)> ?a => "a"
164. $SAFE
165. https://bugs.ruby-lang.org/ issues/8468
167. Refinements
168. Let’s fix some stuff!
169. and & or have the same precedence
170. So many nils floating around
171. pry(main)> "TOP".upcase => "TOP" pry(main)> "TOP".upcase! => nil
172. Optional keyword param?
173. pry(main)> 0.zero? => true pry(main)> 1.zero? => false pry(main)> 0.nonzero? => nil pry(main)> 1.nonzero? => 1
174. x.non_zero?
175. !x.zero?
176. Mutable strings
177. Even JavaScript got this right…
178. Frozen string literals are a step in the right direction
179. ImmutableString
180. Frozen strings?
181. Reassignable constants
182. Reassignable constants
183. pry(main)> A = 5 => 5 pry(main)> A = 6 (pry):39: warning: already initialized constant A (pry):38: warning: previous definition of A was here => 6 pry(main)> Class = 3 (pry):40: warning: already initialized constant Class => 3 pry(main)> Class => 3
185. Class variables
186. class Parent @@class_var = 'parent' def self.print_class_var puts @@class_var end end class Child < Parent @@class_var = 'child' end Parent.print_class_var # => will print "child"
187. Poorly named methods
188. Kernel#puts
189. Kernel#println, anyone?
190. Kernel#print
191. defined?
192. [1] pry(main)> defined? 10 => "expression" [2] pry(main)> defined? Test => nil [3] pry(main)> defined? TrueClass => "constant"
194. Enumerable#include?
195. Enumerable#includes?
196. File.exists is deprecated in favour of File.exist…
198. Perl-style special global variables
199. $:
200. $LOAD_PATH
201. $;
202. $FIELD_SEPARATOR
203. $*
204. $ARGV
205. JRuby defines the English aliases by default
206. Why can’t we do this as soon as Ruby 2.6?
207. Why can’t we do all (most) of this as soon as Ruby 2.6?
208. WTF? Global variables?
210. Even Java doesn’t have globals…
211. Felina
212. One more thing…
213. –Matz “Ruby is no longer my project. It’s the Ruby community’s project.”
214. File tickets
215. Send patches
216. Blog about the issues
217. Speak about the issues
218. Let’s make Ruby better together!
219. Ruby Ruby
220. Thanks! twitter: @bbatsov github: @bbatsov http://batsov.com http://emacsredux.com Grill.rb 2018 Wroclaw, Poland 11.08.2018