DRY 2.0

DRY (Don't Repeat Yourself) is often defined as "No Code Duplication". That's DRY 1.0. The DRY principle really shimes in when you get it to the next level: "No Knowledge Duplication".

This lightning talk was given at #VanRuby Lightning Talk Meetup on Dec 1st 2016.

Transcript

1. @pcreux
   VanRuby - Dec 1st 2016
   DRY 2.0
   

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2. @pcreux
   VanRuby - Dec 1st 2016
   D
   R
   Y
   

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3. @pcreux
   VanRuby - Dec 1st 2016
   D on’t
   R epeat
   Y ourself
   

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4. @pcreux
   VanRuby - Dec 1st 2016
   

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5. @pcreux
   VanRuby - Dec 1st 2016
   “For example, if you’ve duplicated a bit of
   code in many places, the Don’t Repeat
   Yourself (DRY) principle tells you to extract
   the duplication into a single common
   method and then invoke this new method in
   place of the old code.”
   

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6. @pcreux
   VanRuby - Dec 1st 2016
   DRY
   =
   NO Code Duplication
   

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7. @pcreux
   VanRuby - Dec 1st 2016
   

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8. @pcreux
   VanRuby - Dec 1st 2016
   

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9. @pcreux
   VanRuby - Dec 1st 2016
   

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10. @pcreux
    VanRuby - Dec 1st 2016
    DRY
    =
    NO Code Duplication
    

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11. @pcreux
    VanRuby - Dec 1st 2016
    DRY 1.0
    =
    NO Code Duplication
    

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12. @pcreux
    VanRuby - Dec 1st 2016
    DRY 2.0
    =
    NO KNOWLEDGE Duplication
    

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13. @pcreux
    VanRuby - Dec 1st 2016
    

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14. @pcreux
    VanRuby - Dec 1st 2016
    

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15. @pcreux
    VanRuby - Dec 1st 2016
    

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16. @pcreux
    VanRuby - Dec 1st 2016
    Free
    Starter
    Pro99
    Pro199
    Pro499
    

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17. @pcreux
    VanRuby - Dec 1st 2016
    

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18. @pcreux
    VanRuby - Dec 1st 2016
    

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19. @pcreux
    VanRuby - Dec 1st 2016
    Free
    Starter
    Pro99
    Pro199
    Pro499
    NEW PRICING!
    Free
    Startup
    Prime
    Premium
    …
    

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20. @pcreux
    VanRuby - Dec 1st 2016
    

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21. @pcreux
    VanRuby - Dec 1st 2016
    

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22. @pcreux
    VanRuby - Dec 1st 2016
    

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23. @pcreux
    VanRuby - Dec 1st 2016
    

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24. @pcreux
    VanRuby - Dec 1st 2016
    How did we get there?
    
    

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25. @pcreux
    VanRuby - Dec 1st 2016
    KNOWLEDGE Duplication
    
    

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26. @pcreux
    VanRuby - Dec 1st 2016
    Let’s FIX IT!
    
    

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27. @pcreux
    VanRuby - Dec 1st 2016
    

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28. @pcreux
    VanRuby - Dec 1st 2016
    ONE SOURCE of TRUTH
    
    

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29. @pcreux
    VanRuby - Dec 1st 2016
    ExAMPLE:
    POLICY OBJECT
    
    

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30. @pcreux
    VanRuby - Dec 1st 2016
    POLICY OBJECT
    
    Can I do X?
    

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31. @pcreux
    VanRuby - Dec 1st 2016
    POLICY OBJECT
    
    cancancan
    pundit

    …
    

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32. @pcreux
    VanRuby - Dec 1st 2016
    ONE SOURCE of TRUTH
    =
    RICH DATA MODEL
    

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33. @pcreux
    VanRuby - Dec 1st 2016
    

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34. @pcreux
    VanRuby - Dec 1st 2016
    DRY
    =
    NO CODE DUPLICATION
    +
    NO KNOWLEDGE Duplication
    

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