Introduction to Ruby

2011 CCSP

Transcript

1. Introduction to Ruby
   Andrew Liu
   

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2. Ruby is…
   • Designed by Yukihiro Matsumoto (松本行弘)
   – "I wanted a scripting language that was more
   powerful than Perl, and more object-
   oriented than Python. That's why I decided to
   design my own language“
   • An object-oriented scripting language
   • Easy to learn!
   

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3. Philosophy
   • Often people, especially computer engineers, focus
   on the machines. They think, "By doing this, the
   machine will run faster. By doing this, the machine
   will run more effectively. By doing this, the machine
   will something something something."
   • They are focusing on machines. But in fact we need
   to focus on humans, on how humans care about
   doing programming or operating the application of
   the machines. We are the masters. They are the
   slaves.
   

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5. Naming Convention
   • CamelCase
   – Class names, module names
   • ALLCAPITAL
   – Constants
   • words_with_underscore
   – Method names, variable names
   • $ prefix
   – Global variables
   

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6. Everything is an object!
   

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7. Strings
   

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8. String Methods
   

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9. Array
   

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10. What if I want to reverse the array?
    http://ruby-doc.org/core/
    

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12. Range
    

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13. Hash
    

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14. Block
    

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15. How does it work?
    

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16. More About Class
    

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17. More About Class
    

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18. Class
    • Variable
    – @@ prefix: Shared by all class instances
    – @ prefix: Contains instances information
    – No prefix: normal variables
    • Methods
    – self. Prefix: Class methods, as known as static
    method
    – No prefix: Instance methods, must be called with
    a instance
    

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19. Creating Instance
    

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21. Flow Control
    

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22. Cases
    

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23. While
    

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24. For
    

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25. Resources
    • Programming Ruby (Bible)
    – http://www.ruby-
    doc.org/docs/ProgrammingRuby/
    • Ruby API Document
    – http://ruby-doc.org/core/
    • TryRuby
    – http://tryruby.org/
    • Ruby Warrior
    – https://github.com/ryanb/ruby-warrior
    

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