Reading code

As developers, we spend a lot of time learning to write code, while spending little to no time learning to read code. Meanwhile, we often spend more time reading code than actually writing it. Shouldn’t we be spending at least the same amount of time and effort improving this skill? Deliberate practice can help us get better at reading code. Learning how to better read and understand code, can in turn teach us what makes code readable. This might even help us to write code that is easier to read.

In this talk we will discuss the benefits of deliberately practicing reading code in a code reading club or session without an IDE, as well as common strategies to navigate a new codebase and familiarise ourselves with the code using the IDE.

Transcript

1. Reading Code
   ArnhemJUG - August 31st, 2023
   https://maritvandijk.com/
   

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2. Reading Code
   Introduction
   • We spend more time reading code than writing code
   
   

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3. Reading Code
   Introduction
   "developers on average spend as much as 58% of their time comprehending
   existing source code" -
   
   Felienne Hermans,
   
   The Programmer's Brain
   

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4. Reading Code
   Introduction
   We read code when:
   
   • onboarding to a new project
   
   • adding or changing functionality
   
   •
   fi
   xing bugs
   
   • doing code reviews
   
   • reading books, blogs, ...
   
   • etc.
   

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5. Reading Code
   Introduction
   • We spend more time reading code than writing code
   
   • But we don't practice reading code explicitly (much)
   
   

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6. Reading Code
   Introduction
   • What if we practice reading code explicitly?
   

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7. Reading Code
   Introduction
   • Code Reading Club
   https://codereading.club/
   
   

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8. Reading Code
   Introduction
   • Fragment of code (outside an IDE)
   
   • Structured exercises
   

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9. Reading Code
   Introduction
   • So many insights!
   

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10. Reading Code
    Introduction
    • But what about the IDE?
    

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11. Reading Code
    Introduction
    • Di
    ff
    erent strategies / approaches for di
    ff
    erent tasks
    
    • With & without your IDE
    
    

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12. Reading Code
    Agenda
    • The bigger picture
    • Understanding a codebase
    
    • and it's context
    
    • Down to the details
    • Find a place to start
    
    • Search
    
    • Navigate from there
    
    • Understanding a speci
    fi
    c piece of code
    • Hints from your IDE
    
    • Exercises for deliberate practice
    

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13. Reading Code
    Introduction
    • Focus:
    
    • Reading to understand
    • Not to judge
    

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14. Reading Code
    The bigger picture
    

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15. Reading Code
    The bigger picture
    • Onboarding to a new team / code base
    
    

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16. Reading Code
    The bigger picture
    • What does the code do?
    
    

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17. Reading Code
    The bigger picture
    • What is the context?
    

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18. Reading Code
    The bigger picture
    • Background knowledge
    
    • Business domain
    
    • Programming domain
    

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19. Reading Code
    The bigger picture
    • Read the documentation!
    
    • Do some research
    

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20. Reading Code
    The bigger picture
    Strategies:
    
    • Identify components
    
    • Identify relationships / dependencies
    
    • Gain background knowledge
    

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21. Reading Code
    The bigger picture
    • Take notes!
    

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22. Reading Code
    The bigger picture
    But
    fi
    rst:
    
    • Check out the code
    
    • See if you can build it
    

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23. Demo time
    

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24. Reading Code
    The bigger picture
    • Draw your own diagrams
    
    • Write down questions
    
    • Write down suggestions (maybe)
    

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25. Reading Code
    The bigger picture
    Science:
    
    • Chunking
    

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26. Reading Code
    Down to the details
    

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27. Reading Code
    Down to the details
    • Find a starting point
    
    

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28. Reading Code
    Down to the details
    • Search
    

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29. Reading Code
    Down to the details
    • Navigate
    

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30. Demo time
    

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31. Reading Code
    Down to the details
    • Draw your own diagrams
    
    • Write down questions
    
    • Write down suggestions (maybe)
    

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32. Reading Code
    Understanding a piece of code
    

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34. Reading Code
    Understanding a piece of code
    • Exercises
    

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35. Reading Code
    Understanding a piece of code
    • Your IDE can help!
    
    

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36. Reading Code
    Understanding a piece of code
    • Structure
    
    

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37. Reading Code
    Understanding a piece of code
    • Restructure
    
    

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38. Reading Code
    Understanding a piece of code
    • Behavior
    
    

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39. Reading Code
    Understanding a piece of code
    • Context
    
    

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40. Demo time
    

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41. Reading Code
    Next steps
    • What's next?
    
    

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42. Reading code
    Slides & More
    https://maritvandijk.com/presentations/reading-code/
    

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