Ruby_through_Reserved_Words.pdf

Transcript

1. Powered by Rabbit 2.2.1
   Ruby through Reserved
   Words
   Heroku
   Ruby Association
   Yukihiro "Matz" Matsumoto
   まつもとゆきひろ
   @yukihiro_matz
   

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2. Powered by Rabbit 2.2.1
   　
   Ruby has 41 reserved words
   

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3. Powered by Rabbit 2.2.1
   　
   Each reflects (early) design
   decisions
   

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4. Powered by Rabbit 2.2.1
   　
   The story behinds the words
   

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5. Powered by Rabbit 2.2.1
   　
   begin/end
   

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6. Powered by Rabbit 2.2.1
   　
   Comb Style Indentation
   

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7. Powered by Rabbit 2.2.1
   　
   Inherited from Eiffel
   

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8. Powered by Rabbit 2.2.1
   　
   along with rescue, ensure, retry
   

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9. Powered by Rabbit 2.2.1
   　
   break/next/redo
   

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10. Powered by Rabbit 2.2.1
    　
    not continue
    

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11. Powered by Rabbit 2.2.1
    　
    From Perl (shorter)
    

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12. Powered by Rabbit 2.2.1
    　
    class/def
    

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13. Powered by Rabbit 2.2.1
    　
    From Python
    

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14. Powered by Rabbit 2.2.1
    　
    module
    

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15. Powered by Rabbit 2.2.1
    　
    Lisp (Flavors)
    

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16. Powered by Rabbit 2.2.1
    　
    Mix-in
    

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17. Powered by Rabbit 2.2.1
    　
    if/else/elsif
    

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18. Powered by Rabbit 2.2.1
    　
    elsif
    

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19. Powered by Rabbit 2.2.1
    　
    elseif, elif, elsif
    

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20. Powered by Rabbit 2.2.1
    　
    The shortest pronounceable
    

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21. Powered by Rabbit 2.2.1
    　
    then
    

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22. Powered by Rabbit 2.2.1
    　
    The stop words
    

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23. Powered by Rabbit 2.2.1
    　
    then and class methods
    

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24. Powered by Rabbit 2.2.1
    　
    unless
    

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25. Powered by Rabbit 2.2.1
    　
    From Perl
    

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26. Powered by Rabbit 2.2.1
    　
    No elsif or elsunless
    

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27. Powered by Rabbit 2.2.1
    　
    while
    

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28. Powered by Rabbit 2.2.1
    　
    Simple loop
    

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29. Powered by Rabbit 2.2.1
    　
    for/in
    

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30. Powered by Rabbit 2.2.1
    　
    From Python?
    

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31. Powered by Rabbit 2.2.1
    　
    until
    

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32. Powered by Rabbit 2.2.1
    　
    From Perl
    

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33. Powered by Rabbit 2.2.1
    　
    true/false/nil
    

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34. Powered by Rabbit 2.2.1
    　
    Truthy and Falsy
    

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35. Powered by Rabbit 2.2.1
    　
    Three value model
    

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36. Powered by Rabbit 2.2.1
    　
    Inspired by Lisp
    

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37. Powered by Rabbit 2.2.1
    　
    and/or/not
    

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38. Powered by Rabbit 2.2.1
    　
    From Perl
    

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39. Powered by Rabbit 2.2.1
    　
    Only for precedence
    

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40. Powered by Rabbit 2.2.1
    　
    do/yield
    

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41. Powered by Rabbit 2.2.1
    　
    The block
    

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42. Powered by Rabbit 2.2.1
    　
    From CLU (1970s, MIT)
    

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43. Powered by Rabbit 2.2.1
    　
    The biggest invention of Ruby
    

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44. Powered by Rabbit 2.2.1
    　
    rescue/ensure/retry
    

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45. Powered by Rabbit 2.2.1
    　
    Exception handling
    

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46. Powered by Rabbit 2.2.1
    　
    Inspired by Eiffel
    

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47. Powered by Rabbit 2.2.1
    　
    Icon (1970s, U of Arizona)
    

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48. Powered by Rabbit 2.2.1
    　
    Success/Failure model
    

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49. Powered by Rabbit 2.2.1
    　
    return
    

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50. Powered by Rabbit 2.2.1
    　
    From C
    

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51. Powered by Rabbit 2.2.1
    　
    Multiple values (Tuple)
    

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52. Powered by Rabbit 2.2.1
    　
    self/super
    

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53. Powered by Rabbit 2.2.1
    　
    Smalltalk
    

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54. Powered by Rabbit 2.2.1
    　
    alias/undef
    

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55. Powered by Rabbit 2.2.1
    　
    From Sather (1980s, UCB)
    

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56. Powered by Rabbit 2.2.1
    　
    BEGIN/END
    

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57. Powered by Rabbit 2.2.1
    　
    From Awk
    

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58. Powered by Rabbit 2.2.1
    　
    Not recommendation anymore
    

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59. Powered by Rabbit 2.2.1
    　
    __FILE__/__LINE__
    

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60. Powered by Rabbit 2.2.1
    　
    From C (cpp)
    

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61. Powered by Rabbit 2.2.1
    　
    __ENCODING__
    

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62. Powered by Rabbit 2.2.1
    　
    From Ruby1.9 (encoding)
    

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63. Powered by Rabbit 2.2.1
    　
    UCS vs CSI
    

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64. Powered by Rabbit 2.2.1
    　
    Unicode
    

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65. Powered by Rabbit 2.2.1
    　
    BDFL
    

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66. Powered by Rabbit 2.2.1
    　
    Benevolent Dictator For Life
    

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67. Powered by Rabbit 2.2.1
    　
    How to make decisions
    

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68. Powered by Rabbit 2.2.1
    　
    Scope
    Background
    Motivation
    

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69. Powered by Rabbit 2.2.1
    　
    Committee
    

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70. Powered by Rabbit 2.2.1
    　
    Voting
    

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71. Powered by Rabbit 2.2.1
    　
    A ship would climb a mountain
    with many captains
    

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72. Powered by Rabbit 2.2.1
    　
    too many cooks spoil the broth
    

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