Ruby's past, present, and future (RubyConf UY)

Description

"This presentation delves into the past, present, and future of Ruby. This presentation covers various topics including the reason why Ruby was created, Ruby's evolution, its current status, and future plans."

At RubyConf Uruguay 2011
http://rubyconfuruguay.org/en/agenda

Transcript

1. Ruby's past, present, and future Nov 11th, 2011 Shugo Maeda and Yutaka Hara
2. Self introduction • Shugo Maeda (Twitter: @shugomaeda) • A Ruby committer • The co-chairman of the Ruby Association • A director of Network Applied Communication Laboratory Ltd.
5. If you have a question:
6. Self introduction • Yutaka HARA • Twitter ID: @yhara_en • Github ID: yhara – BiwaScheme (Scheme in JavaScript) – ruby-dev.info ([ruby-dev] translation to En) – Esoteric Language designer
7. FAQ: Are you in a Ruby core team? • I'm not, but ... – – – – 　　　　　　　　　　　 ruby-dev.info
8. Esoteric Language • Professional Esoteric Language Designer • Do you know the programming language Whitespace ?
9. programming language ModanShogi • This is a valid Shogi game ▲ ２六歩 △６二銀 ▲６六歩 △７一銀 ▲５六歩 △６二金 ▲ ６八金 △６四歩 ▲６九金 △６三金 ▲６八玉 △５二玉 ▲ ５九金右 △６二金 ▲５八金直 △６三金 ▲５七金 △６二金 ▲ ５九金 △６五歩 ▲６七金 △６三金 ▲５八金 △５一金 ▲ ５九金 △５四歩 ▲５五歩 △５三玉 ▲５七玉 △４二銀 ▲ ６八玉 △５二金 ▲５八金 △５一金 ▲５七金上 △５二金 ▲ ５八金 △５一金 ▲５七金上 △５二金 ▲５八金 △３一銀 ▲ ５七玉 △４二玉 ▲５四歩 △同　金 ▲５五歩 △５一金 ▲ ５四歩 △４一金 ▲５六玉 △５一金 ▲６五玉 △５七歩 ▲ ３六歩 △３二玉 ▲５九金 △６一金 ▲６九金 △５一金 ▲ ５七金 △６二金 ▲５六玉 △６三金 ▲５八金上 △７四金 ▲ ５五玉 △４四歩 ▲３四金 △同　歩 ▲５九金 △３五金 ▲ ４八金 △３六金 ▲６七金 △２六金 ▲３八金 △３六金 ▲ ４八金 △３三玉 ▲５七金上 △２六金 ▲４六金 △２五金 ▲ ４五金 △同　歩 ▲３五歩 △同　金 ▲５七金 △４三金 ▲ ５六金 △４二玉
10. programming language ModanShogi • and prints Hello World. $ cat yowa.modan ▲ ２六歩 △６二銀 ▲６六歩 △７一銀 ▲５六歩 △６二金 ▲ ６八金 △６四歩 ▲６九金 △６三金 ▲６八玉 △５二玉 (..snip..) ▲ ４八金 △３三玉 ▲５七金上 △２六金 ▲４六金 △２五 金 ▲ ４五金 △同　歩 ▲３五歩 △同　金 ▲５七金 △４三金 ▲ ５六金 △４二玉 $ ./bin/shogimodan yowa.modan Hello, world!
11. Topics • Ruby's past, • present, • and future
12. Ruby's past
13. The birth of Ruby • Born on February 24th 1993 – Just the name • Father: Yukihiro Matsumoto, a.k.a. Matz • Godfather: Keiju Ishitsuka
14. How was the name Ruby chosen? keiju> Come to think of it, did you come up with the name of the language? matz> Hmm, if it's similar enough to shells, Tish. matz> But I need a more cool name ... keiju> ruby keiju> Of course, it should be a jewel name matz> Is it taken from ruby annotation? matz> Why should it be a jewel name? matz> Affected by Mitsubishi? keiju> perl matz> I see • Translated log of IRC
15. Ruby 0.49 • The oldest version available – ftp://ftp.ruby-lang.org/pub/ruby/1.0/ruby-0.49.tar.gz – (see [ruby-talk: 206778]) • Released privately in July 1994
16. Hello world in Ruby 0.49 print("Hello world\n") • Is it the same as Ruby 1.9? – Both yes and no – You could not omit parentheses in Ruby 0.49 print "Hello world\n" #=> ERROR!
17. Hello world in Python $ python2.6 -c 'print "hello"' hello $ python3.1 -c 'print "hello"' File "<string>", line 1 print "hello" ^ SyntaxError: invalid syntax
18. print() in Ruby and Python Ruby Python print("a") OK OK OK OK print "a" ERROR OK OK ERROR
19. CoC • Convention over Configuration • Convenience over Consistency • In Python, the print statement was removed for consistency • In Ruby, parenthesis omission was supported for convenience
20. Example code in Ruby 0.49 class greeting # (1) def !=(array) # != can be overridden do array.each using x # (2) @say_hello(x) end fail("error") # (3) end def # (4) def @say_hello(x) # (5) print("Hello, ", x, "!\n") end def end class
21. Example code in Ruby 0.49 (cont'd) protect # (1) g = greeting.new() g != ("Matz" :: "Larry") # (2) print("success\n") resque # (3) print("failed\n") end protect • resque is a typo by Matz (not me!)
22. Already had essential features • ruby-0.49/FAQ + インタプリタであり , 手軽にプログラムできる . + 変数宣言が要らない . + ファイルやストリームなどへの UNIX 的な操作が簡単にできる . + バイナリファイルも扱える . + きちんとしたオブジェクト指向言語である . + 特異メソッドの機能が提供されている . + モジュールによる機能の共有ができる . + 例外処理機能がある . + GC があるのでメモリ管理を気にしなくて済む . + 一貫性のある言語仕様 . + 複雑なデータ構造も扱える . + ダイナミックロードをサポートする ( システムによる ).
23. What was Ruby created for? • For UNIX • For easy object-oriented programming • For fun
24. Ruby for UNIX • Ruby was created for UNIX – Developed on SONY NEWS-OS • Daily scripting like Perl – Not self-contained in contrast to Smalltalk • APIs tied closely to UNIX/C
25. APIs came from UNIX/C • File.open • IO#read • IO#gets • IO#write • Kernel#printf • Kernel#puts • IO#fcntl • IO#ioctl • File.stat • IO.select • Process::Sys.getuid • Process::Sys.setuid • Kernel#fork
26. Better UNIX • Some API's origins are in UNIX/C • However, their behavior is improved • Examples – IO#eof? returns true before read fails while feof(3) does't. – IO.select can be used for buffered IO while select(2) can't.
27. Ruby for object-oriented programming • Problem – OOP is excellent – But too heavy for daily scripting • Solution – Pure object-oriented semantics – Support Non-OO style syntax
28. Pure object-oriented semantics • Pure OO – All data (even integers) are objects – Most operators such as +, - are methods
29. Non-OO style syntax def fib(n) if n < 2 return n else return fib(n - 2) + fib(n - 1) end end puts fib(20) • fib looks like just a function, isn't it?
30. Non-OO syntax + Pure OO semantics • Receivers can be omitted – fib(20) is a short form of self.fib(20) • At top level: – self is an instance of Object – def defines a method in Object
31. Ruby for fun • For Matz's fun – Creating a new language was his dream • For your fun – Who are YOU? – YOU = programmers
32. Shugo's first contact of Ruby • In 1997 • He was a Java programmer – "Please don't throw a stone at me!" • Posted his regexp library in a Java ML • Someone said "Ruby's Regexp is better" • He fell in love with Ruby, threw away Java • Got involved with Ruby development
33. How he learned to stop worrying and love Ruby • His worries were: – Ruby is unpoplular, isn't it? – Ruby is slow, isn't it? – Dynamic typing is unsafe, isn't it?
34. Ruby is unpopular, isn't it? • Yes, it was. – No books – No real world applications – No recruitment for Ruby programmers • But all the more, Ruby was worth learning – Ruby was the "Secret Weapon" – Read Paul Graham's "Beating the Averages"
35. Ruby is slow, isn't it? • Yes, it's slow because it's: – Dynamically typed • Can't use type information for optimization – Pure object oriented • No primitive types like int in Java – Extremely dynamic • Method redefinition etc... • But, the slowness is acceptable – At least for I/O bound applications
36. Dynamic typing is unsafe, isn't it? • Yes, so write test code • Shugo sais... – Ruby programming is like riding a motorcycle • You can go anywhere anytime you want • But you may sometimes slip down – It's fun for me
37. Ruby 1.0 - 1.6 • 1997 - 2002 • Many changes
38. Ruby 1.8 • The first release was on Aug 4th 2003 • Stable • The most successful version of Ruby
39. Ruby 1.8 is past • 1.8.8 – Never released • 1.8.7 – Only bug fixes until June 2012 – Only security fixes until June 2013
40. Some of Shugo's past works • puts • callcc • protected
41. puts • writeln and println were rejected – They came from Pascal and Java – Matz likes neither Pascal nor Java • Shugo proposed the name puts [ruby-dev:771] – It came from C (Matz likes C) – The behavior is a bit weird, though... • puts "A" #=> prints A and \n • puts "A\n" #=> prints A and \n, too • puts [1,2,3]
42. calcc • Introduced callcc into Ruby [ruby-dev:4206] • Provides first class continuations – Came from Scheme (call-with-current- continuation) • Ruby's Black Magic! – (.*)eval – callcc – set_trace_func – ObjectSpace
43. callcc • Saves & loads interpreter state – Used like “goto”, but can jump between methods • Not encouraged to use – Removed from built-in libraries in Ruby 1.9 – It may be completely removed in Ruby 2.0
44. Why is callcc evil? • Objects are mutable in Ruby – callcc doesn't restore the state of objects • C calls and Ruby calls are nested in Ruby – C calls are also restored by callcc – Most C code doesn't take care of it • Even built-in methods used to crash – [ruby-dev:24301] Hash#rehash [ruby-dev:24303] Hash#each [ruby-dev:24378] sort_by [ruby-dev:24432] String#gsub! [ruby-dev:24463] each_with_index [ruby- dev:24487] Dir.glob [ruby-dev:24499] each_slice
45. Example of callcc 01: require "continuation" 02: 03: cont = nil 04: x = callcc { |c| 05: cont = c 06: "first" 07: } 08: p x 09: if x == "first" 10: # go to line 04 with value "second" 11: cont.call("second") 12: end
46. Non-deterministic problems • Problem from the “SICP” book – Baker, Cooper, Fletcher, Miller, and Smith live on different floors of an apartment house that contains only five floors. – Baker does not live on the top floor. – Cooper does not live on the bottom floor. – Fletcher does not live on either the top or the bottom floor. – Miller lives on a higher floor than does Cooper. – Smith does not live on a floor adjacent to Fletcher's. – Fletcher does not live on a floor adjacent to Cooper's. – Where does everyone live?
47. Solution require "amb" a = Amb.new baker = a.choose(1, 2, 3, 4, 5) cooper = a.choose(1, 2, 3, 4, 5) fletcher = a.choose(1, 2, 3, 4, 5) miller = a.choose(1, 2, 3, 4, 5) smith = a.choose(1, 2, 3, 4, 5) a.assert([baker, cooper, fletcher, miller, smith].uniq.length == 5) a.assert(baker != 5) a.assert(cooper != 1) a.assert(fletcher != 1 && fletcher != 5) a.assert(miller > cooper) a.assert((smith - fletcher).abs != 1) a.assert((fletcher - cooper).abs != 1) p [baker, cooper, fletcher, miller, smith]
48. Implementation of Amb class Amb ... def choose(*choices) choices.each { |choice| callcc { |fk| @back << fk return choice } } failure end def failure @back.pop.call end def assert(cond) failure unless cond end
49. protected • Equivalent to Java's protected • Useful to implement binary operators def ==(other) @value == other.value # error if value is private end protected def value; @value; end
50. “abnormal” use of protected • Often seen in Rails applications • Use private instead if possible – private methods can be called from subclasses class ApplicationController < ActionController::Base before_filter :login_required protected # Why not private? def login_required ...
51. Ruby's present
52. Ruby's present • Popularity • JIS/ISO Standard • Ruby 1.9
53. Mainstream Language • TIOBE Index (October 2011) • "A" means mainstream
54. Ruby on Rails • Rails made Ruby more popular • Rails may be more popular than Ruby
55. Difference between Ruby and Rails?
56. Same question in Japan
57. Ruby standard • JIS X 3017 – published on March 22nd 2011 – JIS = Japanese Industrial Standards • ISO/IEC JTC1 Fast-Track procedure – "Voting closed 6 September; it received a 100% approval. Only Japan made comments." • http://grouper.ieee.org/groups/plv/DocLog/300- 399/360-thru-379/22-WG23-N-0364/n0364.pdf
58. Why Ruby standard? • Business reasons – Tranquilizer for enterprise users – Necessary for government procurement • Technical reason – Written specification may help development • We have found some bugs in CRuby:) • The standard may also have bugs:(
59. How Ruby has been standardized • Codified the existing (implicit) specification – No new invention by the standardization WG – Ruby development is kept free • Asked public comments from the community – Over 100 comments – Most of them were reflected in the standard
60. Ruby 1.9 • New implementation • New syntax • Other new features
61. New implementation • YARV = Yet Another Ruby VM • It's now the Ruby VM • Word-code interpreter – The size of opcode and operands is the size of pointers • Made 1.9 faster than Ruby 1.8
62. New syntax • New hash syntax • Extended splat
63. New hash syntax # Normal hash syntax ("hash rocket") h = {:a => 1, :b => 2} # New hash syntax h = {a: 1, b: 2} # e.g. method options (keyword argument) foo opt1: 1, opt2: 2
64. Extended splat # Splat in the middle # (1) def foo(a, *b, c) … # (2) bar(a *b, c) # (3) baz{|a, *b, c| … } # (4) a, *b, c = ary # Multiple splats x = [1,2,3]; y = [4,5,6] ary = *x, *y foo *x, *y
65. Other new features • M17N • Fiber
66. M17N • M17N = multilingualization – UCS (Universal Character Set) Normalization – CSI (Code Set Independent) • Strings are character strings – " ルビー "[0] #=> " ル " – In Ruby 1.8, strings are byte strings – " ルビー "[0] #=> 227
67. Fiber • Semi-coroutine • Like Thread, but you can control when to switch (Fiber.yield)
68. File.open f = File.open # do something with f p f f.close File.open do |f| # do something with f p f end
69. File.open def initialize # ?? end def process # ?? end def finish # ?? end File.open do |f| # do something with f p f end
70. File.open def initialize @f = File.open end def process p @f end def finish @f.close end File.open do |f| # do something with f p f end
71. Takoyaki.open def initialize # ?? end def process # ?? end def finish # ?? end Takoyaki.open do |t| # do something with t p t end
72. Use Fiber def initialize @fiber = Fiber.new{ Takoyaki.open do |t| Fiber.yield(t) # stop execution # do something with t p t end } @t = @fiber.resume end def process; @fiber.resume; end def finish; @t.close; end
73. Ruby 1.9 is present • Everyone should use it now • Migration from Ruby 1.8 to 1.9 is easier than migration from Rails 2 to Rails 3
74. Ruby's future
75. Ruby 2.0 • Had been a vaporware for a long time – Matz mentioned Ruby 2.0 at RubyConf 2001 • Something like Web 2.0?
76. Now Ruby 2.0 is real $ ruby-trunk -v ruby 2.0.0dev (2011-10-31 trunk 33588) [i686-linux] $ fgrep -B2 '2.0' ChangeLog Wed Oct 19 17:06:54 2011 Yukihiro Matsumoto <matz@ ruby-lang.org> * version.h (RUBY_VERSION): finally declare start of 2.0 work! $
77. Ruby 2.0 is future • It's near future • Current schedule – Aug 24th 2012 big-feature freeze – Oct 24th 2012 feature freeze – Feb 24th 2013 2.0 release • Will not be a big change – Matz: 100% upper-compatible to 1.9
78. New features in Ruby 2.0 • Accepted features – Keyword arguments – Module#prepend • Features under discussion – Refinements
79. Keyword arguments # Existing syntax: def foo(opts={}) opts[:opt1] ||= ”foo” if opts[:opt2] … # New syntax: def foo(opt1: "foo", opt2: nil) if opt2 ... # Calling is the same foo(opt1: 1, opt2: 2) – Discussion ongoing: [Redmine #5474]
80. Monkey patching • Redefine methods of existing classes • Extend classes and modules on runtime
81. Use cases of monkey patching • 1. Workaround for a bug of a library • 2. Extensions of built-in classes – Often used for internal DSLs – – • 3. Plugin system like Rails @empty_array.size.should == 0 # Integer#should is added
82. alias_method_chain ActionView::Helpers::RenderingHelper.module_eval do def render_with_update(options = {}, locals = {}, &block) if options == :update update_page(&block) else render_without_update(options, locals, &block) end end alias_method_chain :render, :update end
83. Module#prepend • Replaces alias_method_chain • • • • • • – Discussion ongoing: [Redmine: #1102] module RenderUpdate def render(options = {}, locals = {}, &block) if options == :update update_page(&block) else # call the original RenderingHelper#render super(options, locals, &block) end end end ActionView::Helpers::RenderingHelper.module_eval do prepend RenderUpdate end
84. Refinements • Provides “scoped” monkey patching module MathN refine Fixnum do def /(other) quo(other) end end end module Foo using MathN p 1 / 2 #=> (1/2) end p 1 / 2 #=> 0
85. Considerations for Refinements • Performance issue – It's slow even if refinements are not used • Scope of refinements – Lexical scoping is safe, but not flexible – Do we need refinement propagation? • Discussions: [Redmine: #4085]
86. Who creates Ruby's future? • It's You! • Redmine: – http://redmine.ruby-lang.org/projects/ruby-trunk/ • Mailing list: – http://www.ruby-lang.org/en/community/mailing-lists/
87. Enumerable#lazy • [Redmine: #4890]
89. 2011 Call for grant proposals The Ruby Association is looking to give grants for development projects related to Ruby implementations, libraries and frameworks, including projects that improve existing software.
90. 2011 Call for grant proposals • "looking to give grants for development projects" • Anyone can submit proposals • Grant size: ¥500,000 JPY (≒ $6400 USD) – Selection criteria • Impact on the productivity and performance of Ruby and its environment • Originality and creativity of the project • Feasibility of the project • Details: http://www.ruby-assn.org/en/index.htm
91. Conclusion
92. Ruby's past • Ruby was created for fun • Ruby 1.8 is past
93. Ruby's present • Ruby is now mainstream • Ruby 1.9 is present
94. Ruby's future • Ruby 2.0 is future • You can change it! – http://redmine.ruby-lang.org/projects/ruby-trunk/ – http://www.ruby-lang.org/en/community/mailing-lists/
95. ¡Gracias!
96. Question Escape Ladder • #1 “That is a good question.” • #2 “Let's talk about it later.” • #3