Advanced Ruby for Rails Devs, by Sherif Abushadi

From the October 23rd (2015) SFRails meetup:
http://www.meetup.com/SFRails/events/225588522/

Transcript

1. Advanced Ruby
   for Rails developers
   

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2. What are we talking about?
   Ruby claims to make things easier for developers, but
   sometimes that flexibility feels like complexity.
   For example, Ruby supports 4 different ways to reference
   (and later execute) a piece of code:
   - methods
   - blocks
   - procs
   - lambdas
   

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3. We’re talking about: methods and blocks
   

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4. We’re talking about: dynamic methods
   

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5. We’re talking about: procs and lambdas
   what if ...
   you could treat code as if it were data or an object?
   that’s what procs and lambdas do for you. they let you wrap
   code and pass it around in variables and collections.
   and the two are essentially the same thing except for a
   little syntax and 2 differences in behavior.
   

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6. We’re talking about: procs and lambdas
   both of them are closures (they keep a reference to the
   current context) and respond to the call() method
   

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7. We’re talking about: lambdas
   Lambdas:
   - enforce arity
   - return to the scope in which they were called
   

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8. We’re talking about: procs
   Procs:
   - don’t enforce arity
   - return to the scope in which they were defined
   

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9. Time Check…
   let’s code?
   

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10. We’re talking about: open source for study
    Sample Project: GitLab
    - github.com/gitlabhq/gitlabhq
    - Self hosted Git management software
    Fast and easy Git repositories, hosted either on your own
    or at Gitlab.com. Create projects and repositories, manage
    access and perform collaborative code reviews.
    - 200,000 lines of code and 600 classes among 2800 files
    

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11. We’re talking about: Rails
    link
    sample project: GitLab
    

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12. We’re talking about: Rails
    guides.rubyonrails.org/active_record_querying.html
    

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13. We’re talking about: Rails
    body.call()
    

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14. We’re talking about: Rails sample project: GitLab
    link
    

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15. We’re talking about: Rails
    api.rubyonrails.org
    /classes/AbstractController/Callbacks/ClassMethods.html
    

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16. We’re talking about: Rails
    

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17. summary
    - Ruby let’s you “name” a piece of code to run later.
    - methods and blocks can’t be passed around like objects
    - procs and lambdas can.
    what else?
    - embrace the confusion
    - have faith in your own work
    - keep exploring, playfully
    

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18. - Questions?
    - check out opensourcerails.com
    - thanks!
    Sherif Abushadi
    sherif@devbootcamp.com
    

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