Polishing on "Polished Ruby Programming" #kaigionrails / kaigionrails 2021

Recorded Video: https://youtu.be/EJuKeX7k2rY

Ruby is Nice so We are Nice
https://speakerdeck.com/kakutani/ruby-is-nice-so-we-are-nice
https://youtu.be/NctyqVznddg, https://youtu.be/P7AunfXSOTQ

Polished Ruby Programming
https://www.packtpub.com/product/polished-ruby-programming/9781801072724

Jeremy Evans
https://github.com/jeremyevans
https://twitter.com/jeremyevans0

Lambda Note
https://www.lambdanote.com

n月刊ラムダノート 既刊5冊セット（電子書籍のみ） – 技術書出版と販売のラムダノート https://www.lambdanote.com/collections/frontpage/products/nmonthly-5set-2021-ebook

RubyでつくるRuby ゼロから学びなおすプログラミング言語入門（PDF版のみ） – 技術書出版と販売のラムダノート https://www.lambdanote.com/collections/frontpage/products/ruby-ruby-ebook

エクストリームプログラミング【委託】 - 達人出版会
https://tatsu-zine.com/books/extreme-programming

僕らはエクストリームプログラミングのかけら
https://speakerdeck.com/kakutani/xpmatsuri2019-keynote

Optimizing Partial Backtraces in Ruby 3 by Jeremy Evans - RubyKaigi Takeout 2021
https://rubykaigi.org/2021-takeout/presentations/jeremyevans0.html

Polished Ruby Programming (Amazon.com)
https://www.amazon.com/dp/1801072728

Polished Ruby Programming (Amazon.co.jp)
https://www.amazon.co.jp/dp/B093TH9P7C

Ruby Archaeology by Nick Schwaderer - RubyKaigi Takeout 2021
https://rubykaigi.org/2021-takeout/presentations/schwad4hd14.html
Ruby Archaeology
https://schwaderer-kaigi-2021.herokuapp.com/#33

前提知識が多い。すごくおおい → 最後にまとめて掲載

Rubyist Magazine 0028 号 巻頭言
https://magazine.rubyist.net/articles/0028/0028-ForeWord.html

ﾜﾀｼﾊ ﾙﾋﾞｰｶｲｷﾞ ﾁｮｯﾄﾃﾞｷﾙ / I can organize RubyKaigi a little
https://speakerdeck.com/kakutani/i-can-organize-rubykaigi-a-little

マッドマックス　怒りのデス・ロード (2015) - IMDb
https://www.imdb.com/title/tt1392190/

日本Rubyの会とは | 一般社団法人 日本Rubyの会
https://ruby-no-kai.org/

RubyKaigi Takeout 2021
https://rubykaigi.org/2021-takeout

RubyConf 2021
https://rubyconf.org/

Rubyにとって決定的に足りないものは何だと思いますか？
https://qr.ae/pGVdZc

状況に埋め込まれた学習―正統的周辺参加 Jean Lave, Etienne Wenger
https://www.amazon.co.jp/dp/4782800843

Kaigi on Rails 2021
https://kaigionrails.org/2021/

FJORD BOOT CAMP（フィヨルドブートキャンプ）
https://bootcamp.fjord.jp/

Ginza Rails27 igaiga - Speaker Deck
https://speakerdeck.com/igaiga/ginza-rails27-igaiga?slide=9

Jeremy Evans on Twitter: "Weighing in at 434 pages, "Polished Ruby Programming" will be available for sale on July 9. Currently, it is the #1 New Release in Ruby Computer Programming! This would probably be more impressive if there was more than one new release. :) https://t.co/wFRn4yHbVC @PacktPub" / Twitter
https://twitter.com/jeremyevans0/status/1407513414646198279

Junya Ogura on Twitter: "池袋のジュンク堂、ついにPythonコーナーが独立した。 https://t.co/nAgaXMnBEz" / Twitter
https://twitter.com/junya/status/1437704432372781060

Amazon.co.jp: 角谷 信太郎:作品一覧、著者略歴 https://www.amazon.co.jp/%E8%A7%92%E8%B0%B7%E4%BF%A1%E5%A4%AA%E9%83%8E/e/B0051LA12K

Kakutani Shintaro on Twitter: "売れる本を書けば本は売れる(迫真" / Twitter https://twitter.com/kakutani/status/1382919795939549184

前提知識がおおい。すごくおおい:

WEB+DB PRESS総集編［Vol.1～120］
https://gihyo.jp/book/2021/978-4-297-12215-7

メタプログラミングRuby 第2版
https://www.oreilly.co.jp/books/9784873117430/

オブジェクト指向設計実践ガイド　～Rubyでわかる 進化しつづける柔軟なアプリケーションの育て方
https://gihyo.jp/book/2016/978-4-7741-8361-9

リファクタリング　既存のコードを安全に改善する（第2版）
https://tatsu-zine.com/books/refactoring-2ed

テスト駆動開発
https://tatsu-zine.com/books/test-driven-development

実践テスト駆動開発 テストに導かれてオブジェクト指向ソフトウェアを育てる
https://www.shoeisha.co.jp/book/detail/9784798124582

Rubyのしくみ　Ruby Under a Microscope
https://tatsu-zine.com/books/ruby-under-a-microscope-ja

Clean Architecture 達人に学ぶソフトウェアの構造と設計
https://tatsu-zine.com/books/clean-architecture

リーダブルコード
https://www.oreilly.co.jp/books/9784873115658/

Rubyソースコード完全解説(全文)
https://i.loveruby.net/ja/rhg/book/

Java言語で学ぶデザインパターン入門 第3版
https://www.hyuki.com/dp/

Specification by Example
https://www.manning.com/books/specification-by-example

The RSpec Book
https://www.shoeisha.co.jp/book/detail/9784798121932

The Well-Grounded Rubyist, Third Edition,
https://www.manning.com/books/the-well-grounded-rubyist-third-edition

Exceptional Ruby: Master the Art of Handling Failure in Ruby
https://pragprog.com/titles/ager/exceptional-ruby/

Ruby Performance Optimization: Why Ruby Is Slow, and How to Fix It https://pragprog.com/titles/adrpo/ruby-performance-optimization/

Rubyによるデザインパターン
https://www.amazon.co.jp/dp/4894712857

明解!Ruby―奥深いRubyの文化を身に付けるテクニック
https://www.amazon.co.jp/dp/4864011095

ドメイン特化言語 パターンで学ぶDSLのベストプラクティス46項目
https://www.amazon.co.jp/dp/4864010471

Transcript

1. !LBLVUBOJ
   

   0DU LBJHJPOSBJMT
   POLISHING ON
   
   
   POLISHED RUBY
   

   PROGRAMMING
   

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2. ֯୩৴ଠ࿠
   @kakutani
   

   Rubyist-ist, Keeb zombie⌨🧟
   Ұࣾ
   ೔ຊ3VCZͷձཧࣄ
   ג
   Ӭ࿨γεςϜϚωδϝϯτސ໰
   

   ϑΟϤϧυϒʔτΩϟϯϓސ໰
   ϝΧχΧϧΩʔϘʔυεΠον५׈ऀ
   

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3. 3VCZJTUJTUͱ͸
   

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4. https://speakerdeck.com/kakutani/ruby-is-nice-so-we-are-nice
   📺IUUQTZPVUVCF/DUZR7[OEEH 📺IUUQTZPVUVCF1"VOG94052
   

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5. https://www.packtpub.com/product/polished-ruby-programming/9781801072724
   ݪஶͷిࢠॻ੶͸,JOEMFͰ΋ങ͑Δ͚Ͳɺ1BDLUͷ௚ൢͰങ͏ͱ
   %3.'SFFͷ1%'౳ΛೖखͰ͖Δ͔Β௚ൢ͕͓͢͢Ίͩκ😆📚
   

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6. +FSFNZ͸3VCZ$PNNJUUFSͰɺ3VCZ,BJHJͷ,FZOPUF4QFBLFSͰ͋ΓɺCVHTSVCZMBOHPSHͷνέο
   τΛ௚͠·ͬͯ͘3VCZ1SJ[FΛड৆͍ͯ͠ΔΑɻ$PNNJUUFSͱͯ͠͸৽͠Ίͷ3VCZJTU͚ͩͲɺ3VCZ,BJHJ
   ʹॳΊͯొஃͨ͠ͷ͸3VCZ,BJHJͱ͍͏ݹࢀͳͷͩɻ4FRVFM΍3PEBͳͲΛ΋Γ΋Γϝϯςφϯε͍ͯ͠ΔΑ
   

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7. Lambda Note
   

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8. ʰݚᮎ3VCZϓϩάϥϛϯάʱ
   Ծ
   
   

   ࢮܐࣥߦத
   ຋༁ਐߦத
   ೥ཅय़ ༧ఆ
   
   ֯୩৴ଠ࿠༁ϥϜμϊʔτࣾץο
   ೥݄ిॻЌ൛ൢച։࢝ر๬ ر๬
   
   

   ϖʔδ<্࢙࠷ް>͋ΔͷͰ࣌ؒΛ͍ͩ͘͞ʜ
   
   

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9. https://www.lambdanote.com/collections/frontpage/products/ruby-ruby-ebook
   

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10. ⁋ຊ͞ΜͷʮύλʔϯϚονJO3VCZʯ ݱঢ়ͱ͸গ͠࢓༷͸มΘ͍ͬͯΔ͚Ͳlͳͥz͕ॻ͔Ε͍ͯΔ͔ΒλΠϜϨε
    ͩ
    ΍ɺ֏͞ΜͷʮE3VCZͰָ͠Ή෼ࢄΦϒδΣΫτʯɺNBNFUUFSͷʮʰίϧʔνϯʱͱ͸Կͩͬͨͷ͔ʁʯʮʰܧ
    ଓʱͷͻΈͭʯͱ͍ͬͨ3VCZJTUͷدߘ΍ͳΜ͔೉͠Ίιϑτ΢ΣΞ͕ΒΈͷ࿩͕ͨ͘͞ΜಡΊ͓ͯಘR
    https://www.lambdanote.com/collections/frontpage/products/nmonthly-5set-2021-ebook
    

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11. ങͬͯ͘
    ΕR
    

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12. ໨త
    

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13. lզʑ͸ɺιϑτ΢ΣΞ։ൃʹ͓͍ͯ৽ͨͳࣾձߏ଄
    Λ࡞Γग़͠ɺͦͷͳ͔
    で
    ٕज़తͳߴΈͱ
    ビジ
    ωεͷ
    ビ
    ジ
    ϣϯΛ݁
    び
    ෇͚ɺಠࣗͷ
    バ
    ϦϡʔΛ࣋ͬͨ
    プ
    ϩ
    ダ
    Ϋ
    τ΍αʔ
    ビ
    εΛੜΈग़͢ػձΛ͍࣋ͬͯΔɻ
    

    ͜Ε
    が
    զʑͷڧΈ
    だ
    ɻ
    ɹ91ͷ੒ޭ͸ɺ৴པ
    で
    ͖Διϑτ΢ΣΞͷ͢
    ば
    ΍͍
    ݟੵΓɺ࣮૷ɺ
    デプ
    ϩΠ
    がで
    ͖Δ༏लͳ
    プ
    ϩ
    グ
    ϥϚʔ
    ͷ૿Ճʹ͔͔͍ͬͯΔɻ
    ڧௐ౳͸Ҿ༻ऀʹΑΔ
    
    

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14. https://speakerdeck.com/kakutani/xpmatsuri2019-keynote
    ͜Ε͸ߨԋͷͱ͖ͷഎܠը૾͔͠࢒ͬͯͳͯ͘͝ΊΜ΍Ͱʜ
    

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15. https://www.packtpub.com/product/polished-ruby-programming/9781801072724
    

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16. “This book is aimed at intermediate Ruby programmers
    and focuses on teaching principles of Ruby
    programming, as well as trade-offs to consider when
    making implementation decisions.
    !"#$%&'()*+,-./0123456)*+,-./078/(9:;%<
    =>?@ABCD(EF2GHIAJKLM;3NOAPQ6QRCS
    
    
    — Jeremy Evans (RubyKaigi Takeout 2021)
    

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17. Polished Ruby Programming #ŪŰ
    w ίϛϡχςΟͷlेશత࣮ફऀzʹΑΔٱͼ͞ͷେܕॻ੶
    w ෦ߏ੒ શষ 3VCZରԠ
    w ୈ෦3VCZͷlجૅz ϝιουҾ਺ʹҟ༷ʹ͘Θ͍͠
    
    w ୈ෦࣮ફͷlݪଇͱτϨʔυΦϑz
    w ୈ෦+FSFNZͷओுP
    ff
    UIF3BJMT %# 8FC ηΩϡϦςΟ
    
    w ϖʔδ จষͱίʔυ͔͠ͳ͍ ͔ͨ͘ͳʹਤ͕ແ͍
    
    w l8PSL $PSSFDU 'VOʜBOE'BTUz
    w αϯϓϧίʔυ͕པ΋͍͠ པ΋͗͢͠Δ͔΋😂
    
    

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18. album_artists = {}
    
    
    album_track_artists = {}
    
    
    album_infos.each do |album, track, artist|
    
    
    (album_artists[album] ||= []) << artist
    
    
    (album_track_artists[[album, track]] ||= []) << artist
    
    
    end
    
    
    album_artists.each_value(&:uniq!)
    
    
    པ΋͍͠αϯϓϧίʔυͷ͘͝؆୯ͳྫ
    )BTIͷΤϯτϦʹ഑ྻΛ֨ೲ͢ΔࡍʹɺΤϯτϦ͕OJMͷ৔߹͸ۭ഑ྻͰॳظԽ͔ͯ͠ΒཁૉΛ௥Ճ
    ͢Δͷ͸ߦͰॻ͚ͯ΂ΜΓɺͱ͍͏͜ͱʹ͍ͭͯಛʹຊจͰઆ໌ෆཁͳͷ͕ର৅ಡऀͷதڃऀͩΑ
    

    ଞʹ΋ɺsuper ͷ࢖͍ํ͕΍ͨΒͱ্खͳͷ͕ҹ৅ʹ࢒Γ·ͨ͠ɻࢀߟʹͳΔ😵💫
    

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19. 3VCZ্ڃऀͷϨϏϡʔ
    
    ʮ͍͍ͩͨ஌ͬͯͨʯ Ͱ͠ΐ͏Ͷ
    
    https://www.amazon.com/dp/1801072728
    

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20. 3VCZ্ڃऀͷϨϏϡʔ
    
    ͜Ε͸੢ౢ͞ΜͰ͸ʁlॳֶऀͷਓ͸ؾܰʹ࣭໰Ͱ͖Δ্ڃऀΛ୳ͨ͠΄͏͕͍͍Αz ΍͍͞͠
    
    https://www.amazon.com/dp/1801072728
    

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21. 3VCZ্ڃऀͷϨϏϡʔ
    
    https://www.amazon.co.jp/dp/B093TH9P7C
    ʮ͜ͷͻͱΊͬͪΌ3VCZίϛϡχ
    ςΟʹ͘Θ͍͠ͳʯͱࢥͬͨΒɺ
    

    ϑΝχʔτͰͨ͠
    

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22. Polished Ruby Programming #??
    w ίʔσΟϯάελΠϧ͕ŧŔŕŪŝŬūſʜ
    w checkϝιουͩ ௚આ๏Ͱͳ໋͘ྩ๏ʜͬͯŠŪ
    
    w do…end͔ΒͷϝιουνΣΠϯ͕ؾʹͳͬͪΌ͏
    

    ࢲ͸l5IF8FJSJDI$POWFOUJPOz೿ͳͷͰʜ
    
    w ৘ใݯ͕লུ͞Ε͕ͪͳͷ͕ŝŬūſʜ एׯŰŘŠƃũŝţŪ͔΋
    
    w 3VCZରԠʜແŰƅŦŖƃŵŕŧ ແ3BDUPS ແ3F
    fi
    OFNFOUT
    w લఏ஌͕͓͓͍ࣝɻ͓͓͍͘͢͝
    

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23. “The Weirich Convention”
    https://schwaderer-kaigi-2021.herokuapp.com/#33
    ͘Θ͘͠͸3VCZ,BJHJ5BLFPVUͷ!TIXBEͷl3VCZ"SDIBFPMPHZzΛ؍ͯͶ
    

    IUUQTSVCZLBJHJPSHUBLFPVUQSFTFOUBUJPOTTDIXBEIEIUNM
    do…end ͸खଓ͖తϒϩοΫʹ࢖͏ͱ໌ࣔతʹݴͬͨͷ͸"WEJͳͷ͔ͳ
    
    

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24. લఏ஌͕͓͓͍ࣝɻ͓͓͍͘͢͝ɻ
    

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25. ૊ΈࠐΈΫϥε ม਺ ϝιουҾ
    ਺ ྫ֎ॲཧ ಠࣗΫϥεઃܭ
    3VCP$PQ Ϟδϡʔϧ ϝλϓϩ
    άϥϛϯά %4- ςετ ΠσΟ
    ΦϚςΟοΫ3VCZ ϦϑΝΫλϦ
    ϯά σβΠϯύλʔϯ ࠷దԽʜ
    

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26. ༁ॻઈ൛ ༁͕ඍົ ະ༁ॻ੶ ݹ͍ େ෦ͳͷ΋ڍ͛ͯ·͢ ৭͕ബ͍΍ͭ
    
    

    8%#13&44͸LPͷ࿈ࡌl3VCZͷ΢ϥΨϫz͕ඞಡd
    

    ૯ूฤʹશ෦͸ऩ࿥͞Εͯͳ͍ͷͰԿ߸͔ݸผͰങ͏
    
    

    ʰ3VCZιʔείʔυ׬શղઆʱ 3)(
    ͸΢ΣϒͰશจಡΊ·͢
    

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27. ʰݚᮎ3VCZϓϩάϥϛϯάʱ
    Ծ
    
    

    ࢮܐࣥߦத
    ຋༁ਐߦத
    ೥ཅय़ ༧ఆ
    
    ֯୩৴ଠ࿠༁ϥϜμϊʔτࣾץο
    ೥݄ిॻЌ൛ൢച։࢝ر๬ ر๬
    
    

    ϖʔδ<্࢙࠷ް>͋ΔͷͰ࣌ؒΛ͍ͩ͘͞ʜ
    
    

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28. lզʑ͸ɺιϑτ΢ΣΞ։ൃʹ͓͍ͯ৽ͨͳࣾձߏ଄
    Λ࡞Γग़͠ɺͦͷͳ͔
    で
    ٕज़తͳߴΈͱ
    ビジ
    ωεͷ
    ビ
    ジ
    ϣϯΛ݁
    び
    ෇͚ɺಠࣗͷ
    バ
    ϦϡʔΛ࣋ͬͨ
    プ
    ϩ
    ダ
    Ϋ
    τ΍αʔ
    ビ
    εΛੜΈग़͢ػձΛ͍࣋ͬͯΔɻ
    

    ͜Ε
    が
    զʑͷڧΈ
    だ
    ɻ
    ɹ91ͷ੒ޭ͸ɺ৴པ
    で
    ͖Διϑτ΢ΣΞͷ͢
    ば
    ΍͍
    ݟੵΓɺ࣮૷ɺ
    デプ
    ϩΠ
    がで
    ͖Δ༏लͳ
    プ
    ϩ
    グ
    ϥϚʔ
    ͷ૿Ճʹ͔͔͍ͬͯΔɻ
    ڧௐ౳͸Ҿ༻ऀʹΑΔ
    
    

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29. 3VCZίϛϡχςΟଘଓͷ՝୊
    w 3VCZΤίγεςϜͷൃల
    w 3VCZίϛϡχςΟͷ৽௠୅ँ
    w 3VCZίϛϡχςΟ಺Ͱͷ࿅౓ͷ޲্
    w ࠃ಺Ͱͷ
    3VCZϓϨθϯεͷҡ࣋
    

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30. 3VCZίϛϡχςΟͱ͸
    

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31. http://www.
    fl
    ickr.com/photos/recompile_net/4932459606/
    lίϛϡχςΟͱ͸୭͔ɻ΋ͪΖΜɺ
    ͋ͳͨͷ͜ͱͩɻ͋ͳ͕ͨίϛϡχ
    ςΟͰ͋Γɺ ͦΕҎ֎ʹίϛϡχ
    ςΟ͸͍ͳ͍ɻ͋ͳͨͷΑ͏ͳਓʑͷ
    ू·ΓΛɺίϛϡχςΟͱݺͿͷͩ
    ߴڮ੐ٛ 3VCZJTU.BHB[JOF߸ר಄ݴ
    

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32. ƂŦŢŰ ſűƄŖŜŘŝƄ ŧŔŕŪũƄŝſ / I can organize RubyKaigi a little https://speakerdeck.com/kakutani/i-can-organize-rubykaigi-a-little
    3VCZίϛϡχςΟ͸࿭੕ʹͻͱͭ
    ஍ٿ্ʹແ਺ʹଘࡏ͢Δࠃ΍஍Ҭɺൃ࿩͢Δࣗવݴޠɺڵຯɾؔ৺ʹΑΔαϒίϛϡχςΟͦΕͧΕ͕ॏͳΓͱͭͳ͕ΓΛ࣋
    ͭ͜ͱͰ3VCZʹ·ͭΘΔଟ૚తͳ࣮ફڞಉମΛ஍ٿ্ʹߏ੒͢Δͷͩɻଟ༷Ͱ͋ͬͯ΋෼அ͸͞Εͯ΄͘͠ͳ͍Αɻ3VCZ࠾
    ༻اۀͷ৬৔ʹ΋3VCZͷ࣮ફڞಉମͱͯ͠ͷଆ໘͕͋ΔΑɻ෼அ͞Ε͍ͯͳ͍ͱߟ͑ͯΈͯ͸Ͳ͏ͩΖ͏͔ʁ
    

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33. 3VCZίϛϡχςΟଘଓͷ՝୊
    w 3VCZΤίγεςϜͷൃల
    w 3VCZίϛϡχςΟͷ৽௠୅ँ
    w 3VCZίϛϡχςΟ಺Ͱͷ࿅౓ͷ޲্
    w ࠃ಺Ͱͷ
    3VCZϓϨθϯεͷҡ࣋
    

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34. 3VCZJTU͕޾ͤʹ฻ΒͤΔɺ
    ΦʔηϯςΟοΫͰ͍ΒΕΔ
    

    ΤϯδχΞϦϯά૊৫ΛٻΊͯʜ
    

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35. View Slide

36. 3VCZΤίγεςϜͷൃల
    

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37. 3VCZΤίγεςϜͷൃల
    w ίʔυΛॻ͘
    w ӳޠ BTBMJOHVBGSBODB
    Ͱडൃ৴͢Δ
    w ࠃࡍΧϯϑΝϨϯεͰࣗ෼ͷଘࡏΛࣔ͢
    ͜͜Ͱ͸ʮ޲৺తํ޲ʹҠಈ͢ΔʯԦಓίʔεΛࣔͨ͢Ίʹɺएׯޠฐͷ͋Δ୯७ԽΛ͍ͯ͠ΔΑɻ΋ͪΖΜίϯτ
    ϦϏϡʔγϣϯͷ͔ͨͪ͸͞·͟·Ͱ͋Γɺ3VCZͷ࣮ફڞಉମʹlࢀՃ͢Δz 3VCZJTUʹͳΔ
    ಓ͸ͻͱͭͰ͸ͳ͍Α
    

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38. View Slide

39. View Slide

40. View Slide

41. 3VCZίϛϡχςΟͷ৽௠୅ँ
    

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42. 2VPSBTIZPVIFJ3VCZ଍Γͳ͍<ݕࡧ>
    

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43. lਖ਼౷తपลࢀՃ͸ԁख़࣮ͨ͠ફͷ৔ʹ͓͚ΔͦͷҐ
    ஔʹΑͬͯಈػ͚ͮΒΕͯ޲৺తํ޲ʹҠಈ͢Δɻͦ
    Ε͸૿େ͍ͯ͘͠ࢀՃͷ࢖༻Ձ஋ʹΑͬͯɺ͞Βʹɺ
    ৽ࢀऀͷेશత࣮ફऀʹͳΓ͍ͨͱ͍͏ཉٻʹΑͬ
    ͯɺಈػ͚ͮΒΕΔɻ࣮ફڞಉମʹ͸ྺ࢙ͱൃୡͷα
    ΠΫϧ͕͋ΓɺͦΕࣗମ͸ɺ৽ࢀऀ͕ݹࢀऀʹస਎͢
    Δ͜ͱ͕໨ཱͨͳ͍ܗͰ࣮ફʹͱͬͯඞਢͱͳΔ΍Γ
    ํͰ࠶ੜ࢈͞ΕΔɻ
    

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44. View Slide

45. View Slide

46. https://speakerdeck.com/igaiga/ginza-rails27-igaiga?slide=9
    !JHBJHB͕ۜ࠲3BJMTͰ࿩ͨ͠ͱ͖ͷओʹॳֶऀ޲͚ͷॻ੶Ϛοϓ͕΂ΜΓ
    

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47. 3VCZίϛϡχςΟ಺Ͱͷ
    ɹ࿅౓ͷ޲্
    

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48. lਖ਼౷తपลࢀՃ͸ԁख़࣮ͨ͠ફͷ৔ʹ͓͚ΔͦͷҐ
    ஔʹΑͬͯಈػ͚ͮΒΕͯ޲৺తํ޲ʹҠಈ͢Δɻͦ
    Ε͸૿େ͍ͯ͘͠ࢀՃͷ࢖༻Ձ஋ʹΑͬͯɺ͞Βʹɺ
    ৽ࢀऀͷेશత࣮ફऀʹͳΓ͍ͨͱ͍͏ཉٻʹΑͬ
    ͯɺಈػ͚ͮΒΕΔɻ࣮ફڞಉମʹ͸ྺ࢙ͱൃୡͷα
    ΠΫϧ͕͋ΓɺͦΕࣗମ͸ɺ৽ࢀऀ͕ݹࢀऀʹస਎͢
    Δ͜ͱ͕໨ཱͨͳ͍ܗͰ࣮ફʹͱͬͯඞਢͱͳΔ΍Γ
    ํͰ࠶ੜ࢈͞ΕΔɻ
    

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49. https://www.packtpub.com/product/polished-ruby-programming/9781801072724
    

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50. “This book is aimed at intermediate Ruby programmers
    and focuses on teaching principles of Ruby
    programming, as well as trade-offs to consider when
    making implementation decisions.
    !"#$%&'()*+,-./0123456)*+,-./078/(9:;%<
    =>?@ABCD(EF2GHIAJKLM;3NOAPQ6QRCS
    
    
    — Jeremy Evans (RubyKaigi Takeout 2021)
    

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51. Polished Ruby Programming #ŪŰ
    w ίϛϡχςΟͷlेશత࣮ફऀzʹΑΔٱͼ͞ͷେܕॻ੶
    w ෦ߏ੒ શষ 3VCZରԠ
    w ୈ෦3VCZͷlجૅz ϝιουҾ਺ʹҟ༷ʹ͘Θ͍͠
    
    w ୈ෦࣮ફͷlݪଇͱτϨʔυΦϑz
    w ୈ෦+FSFNZͷओுP
    ff
    UIF3BJMT %# 8FC ηΩϡϦςΟ
    
    w ϖʔδ จষͱίʔυ͔͠ͳ͍ ͔ͨ͘ͳʹਤ͕ແ͍
    
    w l8PSL $PSSFDU 'VOʜBOE'BTUz
    w αϯϓϧίʔυ͕པ΋͍͠ པ΋͗͢͠Δ͔΋😂
    
    

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52. ༁ॻઈ൛ ༁͕ඍົ ະ༁ॻ੶ ݹ͍ େ෦ͳͷ΋ڍ͛ͯ·͢ ৭͕ബ͍΍ͭ
    
    

    8%#13&44͸LPͷ࿈ࡌl3VCZͷ΢ϥΨϫz͕ඞಡd
    

    ૯ूฤʹશ෦͸ऩ࿥͞Εͯͳ͍ͷͰԿ߸͔ݸผͰങ͏
    
    

    ʰ3VCZιʔείʔυ׬શղઆʱ 3)(
    ͸΢ΣϒͰશจಡΊ·͢
    

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53. lզʑ͸ɺιϑτ΢ΣΞ։ൃʹ͓͍ͯ৽ͨͳࣾձߏ଄
    Λ࡞Γग़͠ɺͦͷͳ͔
    で
    ٕज़తͳߴΈͱ
    ビジ
    ωεͷ
    ビ
    ジ
    ϣϯΛ݁
    び
    ෇͚ɺಠࣗͷ
    バ
    ϦϡʔΛ࣋ͬͨ
    プ
    ϩ
    ダ
    Ϋ
    τ΍αʔ
    ビ
    εΛੜΈग़͢ػձΛ͍࣋ͬͯΔɻ
    

    ͜Ε
    が
    զʑͷڧΈ
    だ
    ɻ
    ɹ91ͷ੒ޭ͸ɺ৴པ
    で
    ͖Διϑτ΢ΣΞͷ͢
    ば
    ΍͍
    ݟੵΓɺ࣮૷ɺ
    デプ
    ϩΠ
    がで
    ͖Δ༏लͳ
    プ
    ϩ
    グ
    ϥϚʔ
    ͷ૿Ճʹ͔͔͍ͬͯΔɻ
    ڧௐ౳͸Ҿ༻ऀʹΑΔ
    
    

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54. ࠃ಺Ͱͷ
    
    

    ɹ3VCZϓϨθϯεͷҡ࣋
    

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55. 3VCZJTU͕޾ͤʹ฻ΒͤΔɺ
    ΦʔηϯςΟοΫͰ͍ΒΕΔ
    

    ΤϯδχΞϦϯά૊৫ΛٻΊͯʜ
    

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56. View Slide

57. https://twitter.com/jeremyevans0/status/1407513414646198279
    l "NB[PO
    ͷ3VCZίϯϐϡʔλॻ৽ץϥϯΩϯάͰҐʹͳͬͨΑ
    

    3VCZͷ৽ץ͕࡭Ҏ্͋ͬͨΒ΋ͬͱྑ͔ͬͨΜ͚ͩͲ
    z
    

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58. https://twitter.com/junya/status/1437704432372781060
    

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59. Ͱ΋΍ΔΜͩΑR
    w ຊ͕ॻళʹ͋Δੜ͖ͯ·͢Ξϐʔϧ
    w ࠃ಺ͩͱ೔ຊޠ͡Όͳ͍ͱϦʔν͠ͳ͍
    w ίϩφՒͰిॻؚΊ ٕज़ॻࢢ৔͸ଟগ࣋ͪ௚͠
    ͍ͯΔ Β͍͕͠ಈըੈ୅ͷᎱ಄͕ʜ
    w 3VCZͷຊ͸ͦΜͳʹ਺͕ग़ͳ͍
    w ϋΠΤϯυٕज़ॻ͸ͦΜͳʹ਺͕ग़ͳ͍
    w ຊॻ͸3VCZYϋΠΤϯυٕज़ॻ😇
    

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60. 3VCZYϋΠΤϯυٕज़ॻ😇
    

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61. ࡞ઓ
    

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62. https://twitter.com/kakutani/status/1382919795939549184
    

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63. ചΕΔຊΛॻ͚͹ຊ͸ചΕΔ ഭਅ
    

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64. 3VCZYϋΠΤϯυٕज़ॻ😇
    

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65. 🥺
    

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66. ·ͱΊ
    

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67. ʰݚᮎ3VCZϓϩάϥϛϯάʱ
    Ծ
    
    

    ࢮܐࣥߦத
    ຋༁ਐߦத
    ೥ཅय़ ༧ఆ
    
    ֯୩৴ଠ࿠༁ϥϜμϊʔτࣾץο
    ೥݄ిॻЌ൛ൢച։࢝ر๬ ر๬
    
    

    ϖʔδ͋Δ<্࢙࠷ް>ͷͰ࣌ؒΛ͍ͩ͘͞ʜ
    
    

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68. ങͬͯ͘
    ΕR
    

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69. lզʑ͸ɺιϑτ΢ΣΞ։ൃʹ͓͍ͯ৽ͨͳࣾձߏ଄
    Λ࡞Γग़͠ɺͦͷͳ͔
    で
    ٕज़తͳߴΈͱ
    ビジ
    ωεͷ
    ビ
    ジ
    ϣϯΛ݁
    び
    ෇͚ɺಠࣗͷ
    バ
    ϦϡʔΛ࣋ͬͨ
    プ
    ϩ
    ダ
    Ϋ
    τ΍αʔ
    ビ
    εΛੜΈग़͢ػձΛ͍࣋ͬͯΔɻ
    

    ͜Ε
    が
    զʑͷڧΈ
    だ
    ɻ
    ɹ91ͷ੒ޭ͸ɺ৴པ
    で
    ͖Διϑτ΢ΣΞͷ͢
    ば
    ΍͍
    ݟੵΓɺ࣮૷ɺ
    デプ
    ϩΠ
    がで
    ͖Δ༏लͳ
    プ
    ϩ
    グ
    ϥϚʔ
    ͷ૿Ճʹ͔͔͍ͬͯΔɻ
    ڧௐ౳͸Ҿ༻ऀʹΑΔ
    
    

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70. 3VCZίϛϡχςΟଘଓͷ՝୊
    w 3VCZΤίγεςϜͷൃల
    w 3VCZίϛϡχςΟͷ৽௠୅ँ
    w 3VCZίϛϡχςΟ಺Ͱͷ࿅౓ͷ޲্
    w ࠃ಺Ͱͷ
    3VCZϓϨθϯεͷҡ࣋
    

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71. 3VCZJTU͕޾ͤʹ฻ΒͤΔɺ
    ΦʔηϯςΟοΫͰ͍ΒΕΔ
    

    ΤϯδχΞϦϯά૊৫ΛٻΊͯʜ
    

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72. ങͬͯ͘
    ΕR
    

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73. ʰݚᮎ3VCZϓϩάϥϛϯάʱ
    Ծ
    
    

    ࢮܐࣥߦத
    ຋༁ਐߦத
    ೥ཅय़ ༧ఆ
    
    ֯୩৴ଠ࿠༁ϥϜμϊʔτࣾץο
    ೥݄ిॻЌ൛ൢച։࢝ر๬ ر๬
    
    

    ϖʔδ͋Δ<্࢙࠷ް>ͷͰ࣌ؒΛ͍ͩ͘͞ʜ
    
    

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