Better OO Design in Rails

Slides from a discussion I introduce at Rails Camp 14 and again at rorosyd on 12 November, 2013. Note that these slides only provide a glimpse as they don't include the before and after code examples nor, obviously, the discussion that ensued.

Transcript

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   Better OO Design in Rails
   Keith Pitty
   @keithpitty
   

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   I have a confession …
   

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   which class should be responsible?
   

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   is this class adhering to the
   Single Responsibility Principle?
   

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   “A class should do the smallest possible thing;
   that is, it should have a single responsibility.”
   

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   a better attempt …
   

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   other OO design principles …
   

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   managing dependencies
   

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    creating flexible interfaces
    

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    duck typing
    

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    using inheritance appropriately
    

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    sharing role behaviour with modules
    

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    composition
    

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    how well does Rails support
    good OO design?
    

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    what about functional programming?
    

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    what do you think?
    

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    Some resources
    “Practical Object-Oriented Design in Ruby” by Sandi Metz
    "Objects on Rails" by Avdi Grimm
    "Designing Object-Oriented Software" by Rebecca Wirfs-Brock et al
    "Refactoring: Ruby Edition" by Jay Fields, Shane Harvie and Martin
    Fowler
    "Design Patterns in Ruby" by Russ Olsen
    

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