Python Type Hinting and Static Type Checking

Transcript

1. PyCon Korea 2019
   ੿੸ ఋੑ Ѩࢎ۽
   ؊ ա਷ Python ௏٘ ੘ࢿೞӝ
   ੉ହ൞
   

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2. ߊ಴੗
   blurfx
   • ࣽୌೱ؀೟Ү (2014 ~ )
   • ֏ट௏ܻই (2018.03 ~ 2019.07)
   • ೖ೒ಎ٘ஹಌפ (2019.07 ~ )
   

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3. ౵੉ॆਸ फযೞח ࢎۈٜ਷
   ౵੉ॆਸ ৵ फযೡөਃ?
   

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5. ੿੸ ఋੑ ঱য

   ز੸ ఋੑ ঱য
   

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6. ੿੸ ఋੑ ঱য
   Writing Code Build Test Run/Deploy
   য়ܨܳ ߊѼೞח ҳр
   

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7. ز੸ ఋੑ ঱য
   Writing Code Test Run/Deploy
   য়ܨܳ ߊѼೞח ҳр
   

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8. ੿੸ ఋੑ Ѩࢎо ޖ঺੉Ҋ
   ೞݶ ޖ঺੉ જই૑աਃ?
   

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9. ೐۽ં౟о ੘ਵݶ ѐߊ੗੄ ࣻب ੸Ҋ, ߡӒ੄ ࣻب ੸૑݅
   icons from https://icons8.com
   

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10. ೐۽ં౟о ੘ਵݶ ѐߊ੗੄ ࣻب ੸Ҋ, ߡӒ੄ ࣻب ੸૑݅
    icons from https://icons8.com
    ೐۽ં౟о ழ૑Ҋ ѐߊ੗о ݆ই૑ݶ Ӓ ݅ఀ ߡӒب ݆ই૘פ׮
    

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11. ೐۽ં౟о ੘ਵݶ ѐߊ੗੄ ࣻب ੸Ҋ, ߡӒ੄ ࣻب ੸૑݅
    icons from https://icons8.com
    ೐۽ં౟о ழ૑Ҋ ѐߊ੗о ݆ই૑ݶ Ӓ ݅ఀ ߡӒب ݆ই૘פ׮
    ز੸ ఋੑ ঱য۽ ੘ࢿೠ ௏٘ח ೐۽ં౟о ழ૕ࣻ۾

    п ё୓о যڃ чਸ ঌҊ ੓ח૑ ൨ٜয૘פ׮
    var x 

    

    ... x ?
    

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12. Writing Code
    Static Type
    Checking
    Test Run/Deploy
    ੿੸ ఋੑ ୓௼۽ ఋੑী য়ܨо ੓ח૑ Ѩࢎ
    

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13. ௏٘੄ оةࢿ੉ ৢۄоҊ
    ఋੑਵ۽ ߊࢤೡ ࣻ ੓ח ߡӒܳ ৘ߑ೧઻ਃ
    

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14. ௏٘੄ оةࢿ੉ ৢۄоҊ
    ఋੑਵ۽ ߊࢤೡ ࣻ ੓ח ߡӒܳ ৘ߑ೧઻ਃ
    

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15. To Type or Not to Type:
    Quantifying Detectable Bugs in JavaScript
    http://earlbarr.com/publications/typestudy.pdf
    

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16. http://earlbarr.com/publications/typestudy.pdf
    To Type or Not to Type
    

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17. Conclusion:
    we found that using Flow or TypeScript
    could have prevented 15% of the public
    bugs for public projects on GitHub.
    http://earlbarr.com/publications/typestudy.pdf
    To Type or Not to Type
    

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18. Conclusion:
    we found that using Flow or TypeScript
    could have prevented 15% of the public
    bugs for public projects on GitHub.
    http://earlbarr.com/publications/typestudy.pdf
    To Type or Not to Type
    

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19. ౵੉ॆ਷ ز੸ ఋੑ ঱যੋؘ
    ఋੑਸ যڌѱ ઻ਃ?
    

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20. Function Annotation
    Type Annotation
    Variable Annotation
    Python 3.0+
    Python 3.5+
    Python 3.6+
    

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21. Python 3.6+
    

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22. ఋੑ ൦౴
    

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23. ఋੑ ൦౴
    

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24. ఋੑ ൦౴
    

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25. ఋੑ ൦౴
    

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26. ఋੑ ൦౴
    

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27. • ੿ࣻ৬ ޙ੗ৌ݅ ೲਊೞח ܻझ౟
    • ޙ੗ৌ, पࣻ, ࠗ਎ ࣽࢲ۽ ػ ౚ೒
    • ޙ੗ৌ ః৬ ߄੉౟ чਸ о૓ ٤࣊ցܻ
    • ઁ֎ܼ ೣࣻ৬ ௿ېझ
    ఋੑ ൦౴
    

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28. https://imgflip.com/i/186jmm
    

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29. ఋੑ ൦౴
    

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30. ఋੑ ൦౴
    

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31. ఋੑ ൦౴
    

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32. TypeError: Too many parameters for typing.List; actual 2, expected 1
    ఋੑ ൦౴
    

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33. ఋੑ ൦౴
    

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34. ఋੑ ൦౴
    

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35. ఋੑ ൦౴
    

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36. ఋੑ ൦౴
    

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37. ఋੑ ൦౴
    

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38. ఋੑ ൦౴
    

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39. ఋੑ ൦౴
    

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41. ఋੑ ൦౴
    

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42. ఋੑ ൦౴
    

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45. http://blog.daum.net/junjungirl/109
    

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46. “ no type checking happens at runtime ”
    — PEP 484
    

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48. mypy
    mypy ࢸ஖ೞӝ
    

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49. mypy
    ੿੸ ఋੑ Ѩࢎೞӝ
    

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50. mypy
    ੿੸ ఋੑ Ѩࢎೞӝ
    

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51. mypy
    ੿੸ ఋੑ Ѩࢎೞӝ
    

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53. Incompatible types in assignment (expression has type "str", variable has type "int")
    List item 1 has incompatible type "int"; expected "str"
    List item 2 has incompatible type "float"; expected "str"
    Argument 1 to "append" of "list" has incompatible type "bytes"; expected "str"
    

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54. mypy
    

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55. mypy
    

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56. mypy
    

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57. mypy.readthedocs.io
    ؊ ੗ࣁೠ ղਊ਷...
    

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58. github.com/python/mypy
    

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59. Q & A
    

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60. хࢎ೤פ׮
    iam@xo.dev
    

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