Software Components @ RUG-B

Transcript

1. Software Components
   Why - How - What
   Stephan Hagemann - 2016-11-03 - RUG-B
   @shageman
   

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2. WRITE BETTER
   SOFTW
   ARE
   @shageman
   

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3. @shageman
   

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4. WHAT IS A
   COMPONENT?
   @shageman
   

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5. Labeled Content
   + 

   

   Explicit Dependencies
   @shageman
   

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6. Labeled Content
   + 

   

   Explicit Dependencies
   @shageman
   

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7. @shageman
   

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8. Labeled Content
   + 

   Explicit Dependencies
   @shageman
   

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9. @shageman
   

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10. @shageman
    

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11. @shageman
    

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12. @shageman
    

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13. @shageman
    

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14. A depends on B …
    A
    B
    @shageman
    

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15. thus B can not depend on A
    A
    B
    X
    @shageman
    

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16. and this doesn’t work either
    A
    B
    X
    C
    @shageman
    

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17. X and Y as the same thing
    @shageman
    Y
    X
    

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18. Uncle Bob says
    … I like to draw these lines. Architecture is the art of
    drawing lines. With the interesting rule that once you have
    drawn the lines, all the dependencies that cross that line go
    in the same direction…
    @shageman
    

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19. This is why objects are typically not components…
    @shageman
    

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20. @shageman
    

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21. WHY COMPONENTS?
    @shageman
    

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22. Growing size
    @shageman
    

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23. Exploding complexity
    SIZE
    POSSIBLE
    INTERACTIONS
    @shageman
    

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24. Effect of structure
    VS
    @shageman
    

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25. SIZE
    POSSIBLE
    INTERACTIONS
    Reduced exploding
    complexity
    @shageman
    

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26. @shageman
    

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27. Communication
    @shageman
    

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28. Collaboration
    @shageman
    

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29. Creation
    @shageman
    

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30. Maintenance
    @shageman
    

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31. Comprehension
    @shageman
    

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32. HOW TO IMPLEMENT
    COMPONENTS?
    @shageman
    

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34. Code!!
    @shageman
    

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35. And in other languages?
    Ruby/Rails: Gems + Engines
    Java: Modules
    Go: packages
    Javascript: packages (in npm lingo)
    C: file compiling + linking
    @shageman
    

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36. HOW TO DETERMINE
    WHAT SHOULD BE A
    COMPONENT?
    @shageman
    

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37. SUMMARY
    @shageman
    

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38. Components =
    Labeled Content
    + 

    Explicit Dependencies
    @shageman
    WHAT
    

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39. Components improve…
    communication
    creation
    collaboration
    maintenance
    comprehension
    complexity
    @shageman
    WHY
    

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40. In Ruby and Rails…
    gems and engines can be used as components
    @shageman
    HOW
    

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41. @shageman
    

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42. @shageman
    

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43. https://leanpub.com/cbra/c/rugb
    @shageman
    Discount Code!
    

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44. Further reading
    https://leanpub.com/cbra
    http://cbra.info
    https://github.com/shageman
    http://appcontinuum.io
    @shageman
    

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45. THANKS!
    @shageman
    https://leanpub.com/cbra/c/rugb
    

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