Active Support Secrets

Presented as a lightning talk at Nickel City Ruby Conference 2013 on September 21, 2013.

Video is available at http://www.confreaks.com/videos/2852-nickelcityruby2013-lightning-talk-active-support-secrets

Transcript

1. Active Support Secrets
   

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2. Prem Sichanugrist
   @sikachu
   /sikachu
   

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5. Secrets
   

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9. String
   

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10. String#inquiry
    

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11. today  =  'saturday'
    today  =  today.inquiry
    today.saturday?  #=>  true
    today.sunday?  #=>  false
    

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12. String#squish
    

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13. very_complex_sql  =  <<-­‐SQL
       SELECT  *
       FROM  posts
       WHERE  state='published'
    SQL
    #  =>  "    SELECT  *\n    FROM  posts\n    
    WHERE  state='published'\n"
    

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14. very_complex_sql  =  <<-­‐SQL.squish
       SELECT  *
       FROM  posts
       WHERE  state='published'
    SQL
    #  =>  "SELECT  *  FROM  posts  WHERE  
    state='published'"
    

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15. String#strip_heredoc
    

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16. content  =  <<-­‐README
       Hello
           World!
    README
    #=>  "    Hello\n        World!\n"
    

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17. class  FancyHello
       def  initialize(user)
           if  should_say_hello_to?  user
               content  =  <<-­‐README
                   Hello
                       World!
               README
           end
       end
    end
    #=>  "                Hello\n                    World!\
    

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18. class  FancyHello
       def  initialize(user)
           if  should_say_hello_to?  user
               content  =  <<-­‐README
    Hello
       World!
    README
           end
       end
    end
    #=>  "Hello\n    World!\n"
    

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19. content  =  <<-­‐README.strip_heredoc
       Hello
           World!
    README
    #=>  "Hello\n    World!\n"
    

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20. String#to_date
    String#to_datetime
    String#to_time
    

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21. Date.parse('2013-­‐09-­‐21')
    #=>  Sat,  21  Sep  2013
    '2013-­‐09-­‐21'.to_date
    #=>  Sat,  21  Sep  2013
     
    DateTime.parse('2013-­‐09-­‐21  09:00:00')
    #=>  Sat,  21  Sep  2013  09:00:00  +0000
    '2013-­‐09-­‐21  09:00:00'.to_datetime
    #=>  Sat,  21  Sep  2013  09:00:00  +0000
     
    Time.parse('09:00:00')
    #=>  2013-­‐09-­‐21  09:00:00  -­‐0400
    '09:00:00'.to_time
    #=>  2013-­‐09-­‐21  09:00:00  -­‐0400
    

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22. Hash
    

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23. Hash#transform_keys
    

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24. hash  =  {  foo:  'foo',  bar:  'bar'  }
    #=>  {:foo=>"foo",  :bar=>"bar"}
    hash.transform_keys  {  |key|
       key.to_s.capitalize  }
    #=>  {"Foo"=>"foo",  "Bar"=>"bar"}
    

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25. Object
    

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26. Object#in?
    

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27. STARTING_POKEMONS  =  %w(Chespin  Fennekin  Froakie)
     
    if  STARTING_POKEMONS.include?(current_pokemon)
       #  ...
    end
    

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28. STARTING_POKEMONS  =  %w(Chespin  Fennekin  Froakie)
     
    if  current_pokemon.in?(STARTING_POKEMONS)
       #  ...
    end
    

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29. Object#presence
    

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30. "Hello".presence
    #=>  "Hello"
    nil.presence
    #=>  nil
    

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31. state  =  if  params[:state].present?
       params[:state]
    end
     
    country  =  if  params[:country].present?
       params[:country]
    end
     
    region  =  state  ||  country  ||  'US'
    

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32. region  =  params[:state].presence  ||
       params[:country].presence  ||  'US'
    

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34. http://guides.rubyonrails.org
    

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35. Thank you!
    Prem Sichanugrist (@sikachu)
    Sides: http://bit.ly/as-secret
    

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36. Thank you!
    Prem Sichanugrist (@sikachu)
    Sides: http://bit.ly/as-secret
    I also have some stickers to give away
    

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