Debugging Zen (Lone Star PHP 2015)

Debugging is one of those skills that developers have the hardest time exercising and is also one of the most difficult to teach. It is both a scientific discipline and an art. It often requires you to reach beyond analytical thinking to rely upon your own intuition in order to solve a problem. In this talk, we’ll examine how intuition plays a crucial role in debugging software. You’ll leave with practical pointers on how to tap into intuition as part of your debugging habits and how to combine it with analytical processes to be a better developer.

Transcript

1. Debugging
   Zen
   Ben Ramsey
   

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2. Not Zend!
   

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3. HI, I’M BEN.
   I’m a web craftsman, author,
   and speaker. I build a platform
   for professional photographers
   at ShootProof. I enjoy APIs, open
   source software, organizing user
   groups, good beer, and
   spending time with my family.
   Nashville, TN is my home.
   virtPHP
   ✤ Books
   ✤ Zend PHP Certification
   Study Guide
   ✤ PHP 5 Unleashed
   ✤ Nashville PHP & Atlanta PHP
   ✤ array_column()
   ✤ rhumsaa/uuid library
   ✤ virtPHP
   ✤ PHP League OAuth 2.0 Client
   

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5. Debugging
   Zen?
   

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8. Debugging
   

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9. To search for and eliminate
   malfunctioning elements or errors in
   something, especially a computer
   program or machinery.
   debug
   /diːˈbʌɡ/
   

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10. Zen
    

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11. (colloquial) Extremely relaxed and
    collected.
    (informal) A philosophy of calm,
    reminiscent of that of the Buddhist
    denomination.
    zen
    /zɛn/
    

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12. Just What Is
    Intuition?
    

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13. “Hokey religions and ancient
    weapons are no match for a
    good blaster at your side, kid.”
    —Han Solo
    

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14. Immediate cognition without the use
    of conscious rational processes.
    in·tu·i·tion
    /ˌint(y)o͞oˈiSHən/
    

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17. That’s immediate cognition, and you weren’t
    conscious of any rational process being used.
    

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19. Using your
    Intuition
    

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20. Slow
    Down
    

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21. 1. Stop what you’re doing
    2. Close your eyes
    3. Take a deep breath
    4. Let it out slowly
    

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22. “If you just sit and observe, you will
    see how restless your mind is. If you
    try to calm it, it only makes it worse,
    but over time it does calm, and when
    it does, there’s room to hear more
    subtle things—that’s when your
    intuition starts to blossom and you
    start to see things more clearly and be
    in the present more…”
    

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23. “…Your mind just slows down, and
    you see a tremendous expanse in the
    moment. You see so much more than
    you could see before. It’s a discipline;
    you have to practice it.”
    

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24. Stop Saying
    “I Don’t Know”
    

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25. We shut off our intuition when we
    answer questions with, “I don’t know.”
    

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26. Ask yourself what may be blocking you
    from finding the solution.
    

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27. You must discover the answer.
    

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28. The Problem
    Your Code
    Is in
    

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30. 1. Looking in the wrong place.
    

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31. 2. Wasting time, energy, and resources.
    

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32. 3. Hurting your reputation as a problem solver.
    

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33. First, assume the problem is in your code.
    

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34. Focus on the
    Problem,
    Not aSolution
    

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35. if (A && B) {
    // the problem must be C
    solveUsingD();
    }
    

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36. The symptoms may not indicate the real problem.
    

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38. Always get to the heart of the problem.
    

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39. Debugging the
    Irreproducible
    Problem
    

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40. Do the symptoms point to
    a potential problem area?
    

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41. Sometimes we can’t solve the problem.
    

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42. Rubber
    Ducking
    

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43. 1. Beg, borrow, steal, buy, fabricate or otherwise obtain a
    rubber duck (bathtub variety).
    From a message by Andrew Errington to the University of Canterbury Linux Users Group mailing list, 7 Nov 2002
    http://lists.ethernal.org/oldarchives/cantlug-0211/msg00174.html
    

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44. 2. Place rubber duck on desk and inform it you are just
    going to go over some code with it, if that’s all right.
    From a message by Andrew Errington to the University of Canterbury Linux Users Group mailing list, 7 Nov 2002
    http://lists.ethernal.org/oldarchives/cantlug-0211/msg00174.html
    

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45. 3. Explain to the duck what your code is supposed to do,
    and then go into detail and explain things line by line.
    From a message by Andrew Errington to the University of Canterbury Linux Users Group mailing list, 7 Nov 2002
    http://lists.ethernal.org/oldarchives/cantlug-0211/msg00174.html
    

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46. 4. At some point you will tell the duck what you are
    doing next and then realize that that is not in fact what
    you are actually doing. The duck will sit there serenely,
    happy in the knowledge that it has helped you on your
    way.
    From a message by Andrew Errington to the University of Canterbury Linux Users Group mailing list, 7 Nov 2002
    http://lists.ethernal.org/oldarchives/cantlug-0211/msg00174.html
    

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47. Talk through the problem out loud.
    

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48. Sleep
    on It
    

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49. Your unconscious kicks in while you sleep.
    

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50. Develop With
    Purpose
    

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51. Be intentional.
    

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52. Grok what it is you are doing.
    

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53. Feature for
    future release
    Tag
    1.0
    From this point on, “next
    release” means the release
    after 1.0
    production:
    hotfix 0.2
    Bugfixes from rel.
    branch may be
    Tag
    0.2
    Incorporate bugfix in
    develop
    Only bugfixes!
    Start of release
    branch for
    1.0
    

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56. 59089,74437,42530,62011,36174,116
    95,99933,75496,69517,24908,95047,
    89328,11274,47096,72374,49884,137
    file_ids
    

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57. 59089,74437,42530,62011,36174,116
    95,99933,75496,69517,24908,95047,
    89328,11274,47096,72374,49884,137
    file_ids
    137
    

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58. CREATE TABLE `zip_bundle` (
    `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
    `user_id` int(11) NOT NULL,
    `cart_id` int(11) NOT NULL,
    `file_ids` varchar(100) NOT NULL DEFAULT '',
    PRIMARY KEY (`id`)
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
    

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59. “The difference between science as
    it stands now and the Buddhist
    investigative tradition lies in the
    dominance of the third-person,
    objective method in science and
    the refinement and utilization of
    first-person, introspective methods
    in Buddhist contemplation. In my
    view, the combination of the first-
    person method with the third-
    person method offers the promise
    of a real advance in the scientific
    study of consciousness.”
    

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60. THANK YOU.
    ANY QUESTIONS?
    benramsey.com
    Debugging Zen
    Copyright © 2015 Ben Ramsey
    This work is licensed under Creative Commons Attribution-
    ShareAlike 4.0 International. For uses not covered under this
    license, please contact the author.
    !
    " @ramsey
    # github.com/ramsey
    $ ben@benramsey.com
    If you want to talk more, feel free to
    contact me.
    Ramsey, Ben. “Debugging Zen.” Lone Star PHP. Addison Conference Center,
    Addison, TX. 18 Apr. 2015. Conference presentation.
    This presentation was created using Keynote. The text is set in Adobe
    Minion Pro and Open Sans. The source code is set in Fira Sans Mono.
    The iconography is provided by Font Awesome.
    Unless otherwise noted, all photographs are used by permission
    under a Creative Commons license. Please refer to the Photo Credits
    slide for more information.
    joind.in/13563
    %
    

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61. 1
    2
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    5
    6
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    18
    PHOTO CREDITS
    1. “Zen Stones / Piedras Zen” by Xisco Biblioni, CC BY-NC-SA
    2.0
    2. “Zeev Suraski, Keynote” by S&S Media, CC BY-SA 2.0
    3. “Andi Gutmans” by Stefan Koopmanschap, CC BY-NC-SA 2.0
    4. “Bug on a leaf, in all the glory of f/2.8” by Y.J. Chua, CC BY-
    ND 2.0
    5. “Pagoda garden” by L Hoffheins, CC BY-NC-ND 2.0
    6. “My Brain on MRI” by Julie Falk, CC BY-NC 2.0
    7. “Ripple Effect” by sea turtle, CC BY-NC-ND 2.0
    8. “Steve Jobs Keynote” by Ben Stanfield, CC BY-NC-SA 2.0
    9. “Zen” by Wulf Forrester-Barker, CC BY-NC-SA 2.0
    10. “Annapurna Mountain” by Dave See, CC BY-NC 2.0
    11. “Blue Flower in Barcelona” by Benjamin Grimmnitz, CC BY
    2.0
    12. “Latest DB Schema” by Stanford EdTech, CC BY-NC-ND 2.0
    13. “day 37” by James Gray-King, CC BY-NC 2.0
    14. “Cheetah stalking” by flowcomm, CC BY 2.0
    15. “The Dalai Lama @ Vancouver Peace Summit” by kris krüg,
    CC BY-NC-ND 2.0
    16. “Rubber ducks exposed /2” by Francesco Minciotti, CC BY-
    NC-ND 2.0
    17. “Notes” by Brady Withers, CC BY 2.0
    18. “Sleeping” by MeditationMusic.net, CC BY-NC-SA 2.0
    

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62. 19
    20
    21
    PHOTO CREDITS
    19. STAR WARS © 1977 Lucasfilm, Ltd. Used in accordance
    with Fair Use.
    20. DUNE © 1984 Dino de Laurentiis Corporation. Used in
    accordance with Fair Use.
    21. DUNE © 1984 Dino de Laurentiis Corporation. Used in
    accordance with Fair Use.
    22. “Untitled” by DiamondBack Truck Covers, CC BY-SA 2.0
    22
    

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