人間の直感に対応させた複雑度<Cognitive Complexity>の計測ツールをgo/astで実装してみた

Transcript

1. Bitkey Inc. Connect Product
   Noriki Takahashi
   ਓؒͷ௚ײʹରԠͤͨ͞ෳࡶ౓ͷܭଌπʔϧΛgo/
   astͰ࣮૷ͯ͠Έͨ
   

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2. Outline
   1. ࣗݾ঺հ
   2. ιʔείʔυͷෳࡶ౓
   3. Cognitive Complexityͱ͸ʁ
   4. go/ast ͱ͸ʁ
   5. ෳࡶ౓ܭଌπʔϧ࣮૷
   6. ֶͼͱิ଍
   7. ·ͱΊ
   2
   2
   

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3. 1. ࣗݾ঺հ
   3
   ● ∁ڮయੜ(Noriki Takahashi)
   ○ Twitter: @norinoriki0
   ○ GitHub: nrnrk
   ● גࣜձࣾBitkey
   ○ bitkey platform ͱ͍͏”ΧΪ”ͷϓϥοτϑΥʔϜͷ։ൃ
   ● Go Ͱ։ൃ͍ͯ͠·͕͢ɺ go/ast ͸͜Ε·Ͱ৮ͬͨ͜ͱ͕͋Γ·ͤΜͰͨ͠
   ● झຯ: ਺ֶɾ෺ཧֶ
   ○ zk-SNARKs ͷ਺ֶతͳଆ໘ΛטΈࡅ͘هࣄΛॻ͍ͨΓͯ͠·͢
   ● #gocon Ͱײ૝ͳͲੋඇΑΖ͓͘͠Ͷ͕͍͠·͢ʂ
   

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4. ● Bitkey ͷ3ͭͷࣄۀυϝΠϯ
   ○ Homeʢ฻Β͠ʣ
   ○ Workspaceʢಇ͘ʣ
   ○ Experienceʢඇ೔ৗͷମݧʣ
   ● bitkey platform
   ○ 3ͭͷ hub ΞϓϦέʔγϣϯͷج൫
   1. ࣗݾ঺հ
   4
   ςΫϊϩδʔͷྗͰ͋ΒΏΔ΋ͷΛ
   ҆શͰ ศརͰ ؾ࣋ͪΑ͘ʮͭͳ͛Δʯ
   ͓͢͢Ί͍ͨ͠GoϥΠϒϥϦ౤ථड෇த!
   

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5. ● Bitkey ͷ3ͭͷࣄۀυϝΠϯ
   ○ Homeʢ฻Β͠ʣ
   ○ Workspaceʢಇ͘ʣ
   ○ Experienceʢඇ೔ৗͷମݧʣ
   ● bitkey platform
   ○ 3ͭͷ hub ΞϓϦέʔγϣϯͷج
   ൫
   1. ࣗݾ঺հ
   5
   ςΫϊϩδʔͷྗͰ͋ΒΏΔ΋ͷΛ
   ҆શͰ ศརͰ ؾ࣋ͪΑ͘ʮͭͳ͛Δʯ
   ͓͢͢Ί͍ͨ͠GoϥΠϒϥϦ౤ථड෇த!
   എܠͷ bitkey x Gopher͘ΜͷίϥϘʹ΋஫໨ʂ
   

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6. ιʔείʔυͷෳࡶ౓
   6
   6
   

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7. ಥવͰ͕͢
   Έͳ͞Μ
   7
   7
   2. ιʔείʔυͷෳࡶ౓
   

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8. ෳࡶͳιʔείʔυ͸޷͖Ͱ͔͢ʁ
   8
   8
   2. ιʔείʔυͷෳࡶ౓
   

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9. ෳࡶͳιʔείʔυ͸޷͖Ͱ͔͢ʁ
   9
   9
   2. ιʔείʔυͷෳࡶ౓
   

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10. ࢲ͸ͦΜͳʹ޷͖͡Ό͋Γ·ͤΜ
    10
    10
    2. ιʔείʔυͷෳࡶ౓
    

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11. ࢲ͸ͦΜͳʹ޷͖͡Ό͋Γ·ͤΜ
    11
    11
    2. ιʔείʔυͷෳࡶ౓
    

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12. Ͱ͖Δ͚ͩγϯϓϧʹͯ͠
    อक͠΍͍ͨ͘͢͠
    12
    12
    2. ιʔείʔυͷෳࡶ౓
    

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13. ෳࡶ͕͞ආ͚ΒΕͳ͍ͱ͖͸
    ςετΛॏ఺తʹߦ͍͍ͨ
    13
    13
    2. ιʔείʔυͷෳࡶ౓
    

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14. ͜ΕΒΛܧଓతʹ࣮ݱ͍ͯͨ͘͠Ίʹ
    14
    14
    2. ιʔείʔυͷෳࡶ౓
    

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15. ෳࡶ౓Λఆྔతʹද͍ͨ͠
    15
    15
    2. ιʔείʔυͷෳࡶ౓
    

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16. ௐ΂ͨͱ͜Ζ
    16
    16
    2. ιʔείʔυͷෳࡶ౓
    

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17. ௐ΂ͨͱ͜Ζ
    17
    17
    2. ιʔείʔυͷෳࡶ౓
    

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18. ਓؒͷײ͡Δෳࡶ͞ʹରԠͨ͠
    ࢦඪ͕͋ΔΒ͍͠
    18
    18
    2. ιʔείʔυͷෳࡶ౓
    

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19. ͦΕ͕
    19
    19
    2. ιʔείʔυͷෳࡶ౓
    

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20. Cognitive Complexity
    20
    20
    2. ιʔείʔυͷෳࡶ౓
    

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21. Cognitive Complexity
    21
    21
    2. ιʔείʔυͷෳࡶ౓
    

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22. Cognitive Complexity ͱ͸
    22
    22
    

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23. ● Complexity (ෳࡶ౓) ͱ͸
    3. Cognitive Complexityͱ͸ʁ
    23
    

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24. ● Complexity (ෳࡶ౓) ͱ͸
    ○ ֊૚͕ਂ͍ͱෳࡶʁ
    24
    3. Cognitive Complexityͱ͸ʁ
    

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25. ● Complexity (ෳࡶ౓) ͱ͸
    ○ ֊૚͕ਂ͍ͱෳࡶʁ
    ○ ෼ذ͕ଟ͍ͱෳࡶʁ
    25
    3. Cognitive Complexityͱ͸ʁ
    

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26. ● Complexity (ෳࡶ౓) ͱ͸
    ○ ֊૚͕ਂ͍ͱෳࡶʁ
    ○ ෼ذ͕ଟ͍ͱෳࡶʁ
    ○ ίʔυྔ͕ଟ͍ͱෳࡶʁ
    26
    3. Cognitive Complexityͱ͸ʁ
    

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27. ● Complexity (ෳࡶ౓) ͱ͸
    ○ ֊૚͕ਂ͍ͱෳࡶʁ
    ○ ෼ذ͕ଟ͍ͱෳࡶʁ
    ○ ίʔυྔ͕ଟ͍ͱෳࡶʁ
    ○ ߦ਺͕ଟ͍ͱෳࡶʁ
    27
    3. Cognitive Complexityͱ͸ʁ
    

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28. ● Complexity (ෳࡶ౓) ͱ͸
    ○ ֊૚͕ਂ͍ͱෳࡶʁ
    ○ ෼ذ͕ଟ͍ͱෳࡶʁ
    ○ ίʔυྔ͕ଟ͍ͱෳࡶʁ
    ○ ߦ਺͕ଟ͍ͱෳࡶʁ
    → ஫໨͢ΔϙΠϯτʹΑͬͯࢦඪ͕ҟͳΔ
    28
    3. Cognitive Complexityͱ͸ʁ
    

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29. ● ༷ʑͳෳࡶ౓ͷࢦඪ
    ○ ॥؀తෳࡶ౓ (Cyclomatic Complexity)
    ■ ઢܗతʹಠཱͨ͠ܦ࿏ͷ਺ʹ஫໨ͨ͠ࢦඪ
    ■ (ͬ͘͟Γ͍͏ͱ) ܦ࿏ͷύλʔϯ͕ଟ͍ͱෳࡶͱ൑ఆ
    ○ Halstead ෳࡶ౓
    ■ ௕͞΍“ޠኮ”ͷ਺ʹ஫໨ͨ͠ࢦඪ
    ■ (ͬ͘͟Γ͍͏ͱ) ௕͍΋ͷ΍දݱύλʔϯ͕ଟ͍ͱෳࡶͱ൑ఆ
    29
    3. Cognitive Complexityͱ͸ʁ
    

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30. ● ༷ʑͳෳࡶ౓ͷࢦඪ
    ○ ॥؀తෳࡶ౓ (Cyclomatic Complexity)
    ■ ઢܗతʹಠཱͨ͠ܦ࿏ͷ਺ʹ஫໨ͨ͠ࢦඪ
    ■ (ͬ͘͟Γ͍͏ͱ) ܦ࿏ͷύλʔϯ͕ଟ͍ͱෳࡶͱ൑ఆ
    ○ Halstead ෳࡶ౓
    ■ ௕͞΍“ޠኮ”ͷ਺ʹ஫໨ͨ͠ࢦඪ
    ■ (ͬ͘͟Γ͍͏ͱ) ௕͍΋ͷ΍දݱύλʔϯ͕ଟ͍ͱෳࡶͱ൑ఆ
    30
    3. Cognitive Complexityͱ͸ʁ
    ༗໊ʂ਺ֶతͳϞσϧʹجͮ͘ʂ
    

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31. ● ೝ஌తෳࡶ౓ (Cognitive
    Complexity)
    ○ ਓؒͷ௚ײͱ͍ۙෳࡶ͞Λ໨ࢦͨ͠ࢦඪ
    ○ ίʔυͷઢܗͷྲྀΕΛཚ͢΋ͷʹ஫໨
    ○ 2016೥ʹ஀ੜ
    ■ Cyclomatic Complexity: 1976೥
    31 White Paper: https://sonarsource.com/docs/CognitiveComplexity.pdf
    3. Cognitive Complexityͱ͸ʁ
    

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32. ● ೝ஌తෳࡶ౓ (Cognitive
    Complexity)
    ○ ਓؒͷ௚ײͱ͍ۙෳࡶ͞Λ໨ࢦͨ͠ࢦඪ
    ○ ίʔυͷઢܗͷྲྀΕΛཚ͢΋ͷʹ஫໨
    ○ 2016೥ʹ஀ੜ
    ■ Cyclomatic Complexity: 1976೥
    32 White Paper: https://sonarsource.com/docs/CognitiveComplexity.pdf
    3. Cognitive Complexityͱ͸ʁ
    

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33. “ਓؒͷ௚ײͱ͍ۙ” ͱ͸ʁ
    33
    33
    3. Cognitive Complexityͱ͸ʁ
    

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34. ࣮ྫͰ֬ೝͯ͠ΈΔ
    34
    34
    3. Cognitive Complexityͱ͸ʁ
    

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35. ͜͜Ͱ࣭໰Ͱ͢
    35
    35
    3. Cognitive Complexityͱ͸ʁ
    

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36. ࣍ͷ̎ͭ͸ͲͪΒ͕ෳࡶʁ
    36
    36
    3. Cognitive Complexityͱ͸ʁ
    

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37. 37
    37
    ※ White Paper( https://sonarsource.com/docs/CognitiveComplexity.pdf ) ͷྫΛ Go ʹॻ͖௚ͨ͠΋ͷ
    Ͳ͕ͬͪෳࡶʁ
    3. Cognitive Complexityͱ͸ʁ
    

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38. Cyclomatic Complexity ͷ৔߹
    38
    38
    3. Cognitive Complexityͱ͸ʁ
    

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39. 39
    39
    ※ White Paper( https://sonarsource.com/docs/CognitiveComplexity.pdf ) ͷྫΛ Go ʹॻ͖௚ͨ͠΋ͷ
    3. Cognitive Complexityͱ͸ʁ
    

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40. 40
    40
    ※ White Paper( https://sonarsource.com/docs/CognitiveComplexity.pdf ) ͷྫΛ Go ʹॻ͖௚ͨ͠΋ͷ
    ಉ͡ʂ
    3. Cognitive Complexityͱ͸ʁ
    

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41. Cognitive Complexity ͷ৔߹
    41
    41
    3. Cognitive Complexityͱ͸ʁ
    

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42. 42
    42
    ※ White Paper( https://sonarsource.com/docs/CognitiveComplexity.pdf ) ͷྫΛ Go ʹॻ͖௚ͨ͠΋ͷ
    3. Cognitive Complexityͱ͸ʁ
    

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43. 43
    43
    ※ White Paper( https://sonarsource.com/docs/CognitiveComplexity.pdf ) ͷྫΛ Go ʹॻ͖௚ͨ͠΋ͷ
    େࠩʂ
    3. Cognitive Complexityͱ͸ʁ
    

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44. Cognitive Complexity ͍͍Ͷʂ
    44
    44
    3. Cognitive Complexityͱ͸ʁ
    

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45. 45
    ࢀߟ: White Pager (Appendix B) https://sonarsource.com/docs/CognitiveComplexity.pdf
    ● ෳࡶ౓ܭࢉϧʔϧ
    3. Cognitive Complexityͱ͸ʁ
    

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46. 46
    ࢀߟ: White Pager (Appendix B) https://sonarsource.com/docs/CognitiveComplexity.pdf
    ● ෳࡶ౓ܭࢉϧʔϧ
    1. ҎԼͷཁૉ͕͋Ε͹ +1
    for, switch, goto, if, else, if else,
    goto/break/continue
    3. Cognitive Complexityͱ͸ʁ
    

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47. 47
    ࢀߟ: White Pager (Appendix B) https://sonarsource.com/docs/CognitiveComplexity.pdf
    ● ෳࡶ౓ܭࢉϧʔϧ
    1. ҎԼͷཁૉ͕͋Ε͹ +1
    for, switch, goto, if, else, if else,
    goto/break/continue
    1. ωετ࣌͸ɺ1. ʹ௥ՃͰ
    + (ωετͷਂ͞)
    3. Cognitive Complexityͱ͸ʁ
    

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48. 48
    ࢀߟ: White Pager (Appendix B) https://sonarsource.com/docs/CognitiveComplexity.pdf
    ● ෳࡶ౓ܭࢉϧʔϧ
    1. ҎԼͷཁૉ͕͋Ε͹ +1
    for, switch, goto, if, else, if else,
    goto/break/continue
    1. ωετ࣌͸ɺ1. ʹ௥ՃͰ
    + (ωετͷਂ͞)
    3. Cognitive Complexityͱ͸ʁ
    

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49. ● ෳࡶ౓ܭࢉϧʔϧ
    1. ҎԼͷཁૉ͕͋Ε͹ +1
    for, switch, goto, if, else, if else,
    goto/break/continue
    1. ωετ࣌͸ɺ1. ʹ௥ՃͰ
    + (ωετͷਂ͞)
    49
    ࢀߟ: White Pager (Appendix B) https://sonarsource.com/docs/CognitiveComplexity.pdf
    for ΍ if Ͱෳࡶ౓͸૿Ճ
    3. Cognitive Complexityͱ͸ʁ
    

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50. ● ෳࡶ౓ܭࢉϧʔϧ
    1. ҎԼͷཁૉ͕͋Ε͹ +1
    for, switch, goto, if, else, if else,
    goto/break/continue
    1. ωετ࣌͸ɺ1. ʹ௥ՃͰ
    + (ωετͷਂ͞)
    50
    ࢀߟ: White Pager (Appendix B) https://sonarsource.com/docs/CognitiveComplexity.pdf
    3. Cognitive Complexityͱ͸ʁ
    ωετͷਂ͕͞Ճࢉ஋ʹ
    

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51. ● ෳࡶ౓ܭࢉϧʔϧ
    1. ҎԼͷཁૉ͕͋Ε͹ +1
    for, switch, goto, if, else, if else,
    goto/break/continue
    1. ωετ࣌͸ɺ1. ʹ௥ՃͰ
    + (ωετͷਂ͞)
    51
    ࢀߟ: White Pager (Appendix B) https://sonarsource.com/docs/CognitiveComplexity.pdf
    3. Cognitive Complexityͱ͸ʁ
    early return ͸OK
    continue ͸NG
    

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52. Go ͷϓϩάϥϜΛܭଌͯ͠Έ͍ͨʂ
    52
    52
    3. Cognitive Complexityͱ͸ʁ
    

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53. ੩తղੳπʔϧΛ࡞ΔͨΊͷ
    ϥΠϒϥϦ͸ͨ͘͞Μ͋Δ
    53
    53
    3. Cognitive Complexityͱ͸ʁ
    

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54. golang.org/x/tools/go/analysis
    golang.org/x/tools/go/ast/inspector
    golang.org/x/tools/go/ast/astuil
    golang.org/x/tools/go/ssa
    …
    54
    54
    3. Cognitive Complexityͱ͸ʁ
    

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55. ੩తղੳॳ৺ऀ͔Β͢Δͱ..
    55
    55
    3. Cognitive Complexityͱ͸ʁ
    

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56. ֓೦͕ଟͯ͘ཧղ͕େม͔΋...
    56
    56
    3. Cognitive Complexityͱ͸ʁ
    

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57. 57
    57
    3. Cognitive Complexityͱ͸ʁ
    ֓೦͕ଟͯ͘ཧղ͕େม͔΋...
    

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58. େݩʹ͋Δඪ४ͷ go/ast
    ͚ͩͰ΋े෼࡞ΕΔ
    58
    58
    3. Cognitive Complexityͱ͸ʁ
    

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59. ੩తղੳͷ࠷ॳͷҰาͱͯ͠
    جૅͱͯ͠ go/ast Λཧղ͍ͨ͠...!
    59
    59
    3. Cognitive Complexityͱ͸ʁ
    

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60. Cognitive Complexity ܭଌπʔϧ
    go/ast Ͱ࣮૷ͯ͠جຊΛཧղ͠Α͏
    60
    60
    3. Cognitive Complexityͱ͸ʁ
    

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61. Cognitive Complexity ܭଌπʔϧ
    go/ast Ͱ࣮૷ͯ͠جຊΛཧղ͠Α͏
    61
    61
    3. Cognitive Complexityͱ͸ʁ
    

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62. go/ast ͱ͸ʁ
    62
    62
    

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63. ● go/ast ͱ͸
    ○ ߏจ໦Λදݱ͢ΔͨΊʹ࢖༻͞ΕΔܕ͕ೖͬͨύοέʔδ
    ○ linter Λ࡞Δͱ͖ͳͲʹར༻͞Ε͍ͯΔ
    4. go/ast ͱ͸ʁ
    63
    

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64. ● go/ast ͱ͸
    ○ ߏจ໦Λදݱ͢ΔͨΊʹ࢖༻͞ΕΔܕ͕ೖͬͨύοέʔδ
    ○ linter Λ࡞Δͱ͖ͳͲʹར༻͞Ε͍ͯΔ
    ● AST(ந৅ߏจ໦)ͱ͸
    ○ ιʔείʔυΛѻ͍΍͍͢Α͏ʹ໦ߏ଄ʹͨ͠΋ͷ
    ○ Abstract Syntax Tree ͷུ
    4. go/ast ͱ͸ʁ
    64
    

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65. (ந৅)ߏจ໦ͬͯ݁ہͳΜͩ?
    65
    65
    4. go/ast ͱ͸ʁ
    

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66. ιʔείʔυͷίϯύΠϧ࣌ͷ
    ྲྀΕͰ֬ೝͯ͠ΈΔ
    66
    66
    4. go/ast ͱ͸ʁ
    

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67. 67
    67
    ιʔείʔυ
    ࣮ߦϑΝΠϧ
    ίϯύΠϧ࣌ͷॲཧͷྲྀΕ
    4. go/ast ͱ͸ʁ
    ίϯύΠϧ
    

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68. 68
    68
    ιʔείʔυ
    ߏจ໦
    ࣮ߦϑΝΠϧ
    ࣈ۟ղੳ & ߏจղੳ
    ҙຯղੳ & ࠷దԽ
    ίϯύΠϧ࣌ͷॲཧͷྲྀΕ
    4. go/ast ͱ͸ʁ
    

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69. 69
    69
    ιʔείʔυ
    ߏจ໦
    ࣮ߦϑΝΠϧ
    func main() {
    result := `apple` + `pen`
    …
    }
    ࣈ۟ղੳ & ߏจղੳ
    ҙຯղੳ & ࠷దԽ
    ίϯύΠϧ࣌ͷॲཧͷྲྀΕ
    4. go/ast ͱ͸ʁ
    

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70. 70
    70
    ιʔείʔυ
    ߏจ໦
    ࣮ߦϑΝΠϧ
    func main() {
    result := `apple` + `pen`
    …
    }
    ࣈ۟ղੳ & ߏจղੳ
    ҙຯղੳ & ࠷దԽ
    ίϯύΠϧ࣌ͷॲཧͷྲྀΕ
    4. go/ast ͱ͸ʁ
    apple pen
    +
    

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71. 71
    71
    ιʔείʔυ
    ߏจ໦
    ࣮ߦϑΝΠϧ
    func main() {
    result := `apple` + `pen`
    …
    }
    ࣈ۟ղੳ & ߏจղੳ
    ҙຯղੳ & ࠷దԽ
    ίϯύΠϧ࣌ͷॲཧͷྲྀΕ
    4. go/ast ͱ͸ʁ
    apple pen
    +
    

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72. 72
    72
    ιʔείʔυ
    ߏจ໦
    ࣮ߦϑΝΠϧ
    func main() {
    result := `apple` + `pen`
    …
    }
    ࣈ۟ղੳ & ߏจղੳ
    ҙຯղੳ & ࠷దԽ
    ίϯύΠϧ࣌ͷॲཧͷྲྀΕ
    4. go/ast ͱ͸ʁ
    apple pen
    +
    

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73. 73
    73
    ιʔείʔυ
    ߏจ໦
    ࣮ߦϑΝΠϧ
    func main() {
    result := `apple` + `pen`
    …
    }
    ࣈ۟ղੳ & ߏจղੳ
    ҙຯղੳ & ࠷దԽ
    ίϯύΠϧ࣌ͷॲཧͷྲྀΕ
    ߏ଄Խ͞Ε͍ͯΔ͓͔͛Ͱ...
    ίʔυΛνΣοΫ͢Δॲཧ͕ॻ͖΍͍͢
    (ྫ: ه๏ͷνΣοΫɺύοέʔδґଘͳͲ)
    AST = go/ast Ͱ͜ͷߏ଄Λར༻Ͱ͖
    Δ
    4. go/ast ͱ͸ʁ
    apple pen
    +
    

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74. ஫: ࣮͸Go ͷίϯύΠϥͰ͸ go/ast Λ࢖͍ͬͯͳ͍
    → go/ast ͸੩తղੳπʔϧͳͲͰར༻͞Ε͍ͯΔ
    74
    74
    4. go/ast ͱ͸ʁ
    

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75. ● go/ast Ͱදݱ͞ΕΔߏ଄
    75
    4. go/ast ͱ͸ʁ
    

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76. ● go/ast Ͱදݱ͞ΕΔߏ଄
    76
    Node
    Node
    Node
    Node
    Node Node
    4. go/ast ͱ͸ʁ
    

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77. ● go/ast Ͱදݱ͞ΕΔߏ଄
    77
    Node
    Node
    Node
    Node
    Node Node
    4. go/ast ͱ͸ʁ
    ۩ମྫΛ go/ast ͷυΩϡϝϯτͰνΣοΫʂ
    

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78. AssignStmt
    BinaryExpr
    BlockStmt
    BranchStmt
    CallExpr
    DeclStmt
    DeferStmt
    EmptyStmt
    ExprStmt
    ForStmt
    78
    78
    4. go/ast ͱ͸ʁ
    FuncDecl
    GenDecl
    GoStmt
    IfStmt
    ImportSpec
    IncDecStmt
    IndexExpr
    KeyValueExpr
    LabeledStmt
    ParenExpr
    RangeStmt
    ReturnStmt
    SelectStmt
    SelectorExpr
    SendStmt
    SliceExpr
    StartExpr
    SwitchStmt
    TypeAssertExpr
    TypeSpec
    TypeSwitchStmt
    UnaryExpr
    ValueSpec
    ͳͲ
    

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79. AssignStmt
    BinaryExpr
    BlockStmt
    BranchStmt
    CallExpr
    DeclStmt
    DeferStmt
    EmptyStmt
    ExprStmt
    ForStmt
    79
    79
    4. go/ast ͱ͸ʁ
    FuncDecl
    GenDecl
    GoStmt
    IfStmt
    ImportSpec
    IncDecStmt
    IndexExpr
    KeyValueExpr
    LabeledStmt
    ParenExpr
    RangeStmt
    ReturnStmt
    SelectStmt
    SelectorExpr
    SendStmt
    SliceExpr
    StartExpr
    SwitchStmt
    TypeAssertExpr
    TypeSpec
    TypeSwitchStmt
    UnaryExpr
    ValueSpec
    ͳͲ
    େྔ...!
    Θ͚͕Θ͔Βͳ͍...
    

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80. AssignStmt
    BinaryExpr
    BlockStmt
    BranchStmt
    CallExpr
    DeclStmt
    DeferStmt
    EmptyStmt
    ExprStmt
    ForStmt
    80
    80
    4. go/ast ͱ͸ʁ
    FuncDecl
    GenDecl
    GoStmt
    IfStmt
    ImportSpec
    IncDecStmt
    IndexExpr
    KeyValueExpr
    LabeledStmt
    ParenExpr
    RangeStmt
    ReturnStmt
    SelectStmt
    SelectorExpr
    SendStmt
    SliceExpr
    StartExpr
    SwitchStmt
    TypeAssertExpr
    TypeSpec
    TypeSwitchStmt
    UnaryExpr
    ValueSpec
    ͳͲ
    ΜʁΑ͘ݟΔͱ຤ඌ͕ڞ௨͍ͯ͠Δ΍͕ͭ͋Δͳ
    

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81. AssignStmt
    BinaryExpr
    BlockStmt
    BranchStmt
    CallExpr
    DeclStmt
    DeferStmt
    EmptyStmt
    ExprStmt
    ForStmt
    81
    81
    4. go/ast ͱ͸ʁ
    FuncDecl
    GenDecl
    GoStmt
    IfStmt
    ImportSpec
    IncDecStmt
    IndexExpr
    KeyValueExpr
    LabeledStmt
    ParenExpr
    RangeStmt
    ReturnStmt
    SelectStmt
    SelectorExpr
    SendStmt
    SliceExpr
    StartExpr
    SwitchStmt
    TypeAssertExpr
    TypeSpec
    TypeSwitchStmt
    UnaryExpr
    ValueSpec
    ͳͲ
    

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82. AssignStmt
    BinaryExpr
    BlockStmt
    BranchStmt
    CallExpr
    DeclStmt
    DeferStmt
    EmptyStmt
    ExprStmt
    ForStmt
    82
    82
    4. go/ast ͱ͸ʁ
    FuncDecl
    GenDecl
    GoStmt
    IfStmt
    ImportSpec
    IncDecStmt
    IndexExpr
    KeyValueExpr
    LabeledStmt
    ParenExpr
    RangeStmt
    ReturnStmt
    SelectStmt
    SelectorExpr
    SendStmt
    SliceExpr
    StartExpr
    SwitchStmt
    TypeAssertExpr
    TypeSpec
    TypeSwitchStmt
    UnaryExpr
    ValueSpec
    ͳͲ
    υΩϡϝϯτ͸ABCॱʹฒΜͰ͍Δ͕
    ߏ଄ମ໊ͷ຤ඌʹ஫໨ͯ͠෼ྨ͢ΔͱΘ͔Γ΍͍͢
    

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83. Node ͷ෼ྨ
    ɾ Stmt : จ (Statement)
    ɾ Expr : ࣜ(Expression)
    ɾ Decl : એݴ(Declaration)
    ɾ Spec : εϖοΫ(Specification)
    ɾ Type : ܕ
    ɾ Lit : Ϧςϥϧ(Literal)
    etc…
    ● go/ast Ͱදݱ͞ΕΔߏ଄
    83
    Node
    Node
    Node
    Node
    Node Node
    4. go/ast ͱ͸ʁ
    

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84. Node ͷ෼ྨ
    ɾ Stmt : จ (Statement)
    ɾ Expr : ࣜ(Expression)
    ɾ Decl : એݴ(Declaration)
    ɾ Spec : εϖοΫ(Specification)
    ɾ Type : ܕ
    ɾ Lit : Ϧςϥϧ(Literal)
    etc…
    ● go/ast Ͱදݱ͞ΕΔߏ଄
    84
    Node
    Node
    Node
    Node
    Node Node
    4. go/ast ͱ͸ʁ
    ιʔείʔυ্΋࣮͸ interface ͕
    ͪΌΜͱఆٛ͞Ε͍ͯΔ
    

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85. ࣮ྫͰνΣοΫʂ
    85
    85
    4. go/ast ͱ͸ʁ
    

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86. 4. go/ast ͱ͸ʁ
    gopher.go
    

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87. 4. go/ast ͱ͸ʁ
    gopher.go
    main.go : “gopher.go” ͷ AST Λग़ྗ͢Δ
    

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88. 4. go/ast ͱ͸ʁ
    gopher.go
    main.go : “gopher.go” ͷ AST Λग़ྗ͢Δ
    AST ʹม׵
    AST Λग़ྗ
    

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89. File
    GenDecl
    FuncDecl
    Ident
    BlockStm
    t
    CallExpr
    ImportSpec
    SelectorExpr
    BasicLit
    Ident
    FuncType
    FieldList
    BasicLit
    Ident Ident
    4. go/ast ͱ͸ʁ
    gopher.go
    

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90. File
    GenDecl
    FuncDecl
    Ident
    BlockStm
    t
    CallExpr
    ImportSpec
    SelectorExpr
    BasicLit
    Ident
    FuncType
    FieldList
    BasicLit
    Ident Ident
    main
    import (શମ)
    import (1ͭ)
    “fmt” () (Ҿ਺ͳ͠)
    “gopher
    ”
    func
    {}
    fmt Printl
    n
    “Gopher!
    !”
    ( )
    .
    4. go/ast ͱ͸ʁ
    gopher.go
    

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91. File
    GenDecl
    FuncDecl
    Ident
    BlockStm
    t
    CallExpr
    ImportSpec
    SelectorExpr
    BasicLit
    Ident
    FuncType
    FieldList
    BasicLit
    Ident Ident
    main
    import (શମ)
    import (1ͭ)
    “fmt” () (Ҿ਺ͳ͠)
    “gopher
    ”
    func
    {}
    fmt Printl
    n
    “Gopher!
    !”
    ( )
    File ͕ϧʔτʂ
    .
    4. go/ast ͱ͸ʁ
    gopher.go
    

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92. File
    GenDecl
    FuncDecl
    Ident
    BlockStm
    t
    CallExpr
    ImportSpec
    SelectorExpr
    BasicLit
    Ident
    FuncType
    FieldList
    BasicLit
    Ident Ident
    main
    import (શମ)
    import (1ͭ)
    “fmt” () (Ҿ਺ͳ͠)
    “gopher
    ”
    func
    {}
    .
    fmt Printl
    n
    “Gopher!
    !”
    ( )
    File ͕ϧʔτʂ
    4. go/ast ͱ͸ʁ
    gopher.go
    

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93. File
    GenDecl
    FuncDecl
    Ident
    BlockStm
    t
    CallExpr
    ImportSpec
    SelectorExpr
    BasicLit
    Ident
    FuncType
    FieldList
    BasicLit
    Ident Ident
    main
    import (શମ)
    import (1ͭ)
    “fmt” () (Ҿ਺ͳ͠)
    “gopher
    ”
    func
    {}
    .
    fmt Printl
    n
    “Gopher!
    !”
    ( )
    File ͕ϧʔτʂ
    4. go/ast ͱ͸ʁ
    gopher.go
    

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94. File
    GenDecl
    FuncDecl
    Ident
    BlockStm
    t
    CallExpr
    ImportSpec
    SelectorExpr
    BasicLit
    Ident
    FuncType
    FieldList
    BasicLit
    Ident Ident
    main
    import (શମ)
    import (1ͭ)
    “fmt” () (Ҿ਺ͳ͠)
    “gopher
    ”
    func
    {}
    .
    fmt Printl
    n
    “Gopher!
    !”
    ( )
    File ͕ϧʔτʂ
    4. go/ast ͱ͸ʁ
    gopher.go
    

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95. File
    GenDecl
    FuncDecl
    Ident
    BlockStm
    t
    CallExpr
    ImportSpec
    SelectorExpr
    BasicLit
    Ident
    FuncType
    FieldList
    BasicLit
    Ident Ident
    main
    import (શମ)
    import (1ͭ)
    “fmt” () (Ҿ਺ͳ͠)
    “gopher
    ”
    func
    {}
    .
    fmt Printl
    n
    “Gopher!
    !”
    ( )
    File ͕ϧʔτʂ
    4. go/ast ͱ͸ʁ
    gopher.go
    

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96. ෳࡶ౓ܭଌπʔϧ࣮૷
    96
    96
    

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97. ● ෳࡶ౓ܭଌπʔϧ
    ○ ιʔείʔυ͔Β֤ؔ਺͝ͱͷ Cognitive Complexity Λܭࢉ͢Δ
    5. ෳࡶ౓ܭଌπʔϧ࣮૷
    97
    

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98. ● ෳࡶ౓ܭଌπʔϧ
    ○ ιʔείʔυ͔Β֤ؔ਺͝ͱͷ Cognitive Complexity Λܭࢉ͢Δ
    ● શମͷߏ଄
    1. ιʔείʔυ͔ΒASTΛੜ੒
    2. AST͔Βؔ਺ͷϊʔυͷΈநग़
    3. ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
    98
    5. ෳࡶ౓ܭଌπʔϧ࣮૷
    

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99. ᶃ ιʔείʔυ͔ΒASTΛੜ੒
    99
    99
    5. ෳࡶ౓ܭଌπʔϧ࣮૷
    

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100. ᶃ ιʔείʔυ͔ΒASTΛੜ੒
     100
     100
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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101. ᶃ ιʔείʔυ͔ΒASTΛੜ੒
     101
     101
     ϧʔτʹͳΔ Node (File) ͕औಘͰ͖Δ
     ଞͷNode͸͔͜͜ΒͨͲΔ͜ͱ͕Ͱ͖Δ
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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102. ᶄ AST͔Βؔ਺ͷϊʔυͷΈநग़
     102
     102
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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103. ᶄ AST͔Βؔ਺ͷϊʔυͷΈநग़
     103
     103
     ᶃ ͷ File (Node)
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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104. ᶄ AST͔Βؔ਺ͷϊʔυͷΈநग़
     104
     104
     ίʔυͷதͷؔ਺ͷΈΛऔΓग़͢
     → ᶅ Ͱؔ਺ຖʹॲཧ
     ᶃ ͷ File (Node)
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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105. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     105
     105
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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106. 3-1. ෳࡶ౓ͷܭࢉϧʔϧ࠶֬ೝ
     106
     106
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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107. ● ෳࡶ౓ܭࢉϧʔϧ(࠶ܝ)
     1. ҎԼͷཁૉ͕͋Ε͹ +1
     for, switch, goto, if, else, if else,
     goto/break/continue
     1. ωετ࣌͸ɺ1. ʹ௥ՃͰ
     + (ωετͷਂ͞)
     107
     ࢀߟ: White Pager (Appendix B) https://sonarsource.com/docs/CognitiveComplexity.pdf
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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108. 3-2. ॲཧͷશମ૾
     108
     108
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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109. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     109
     109
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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110. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     110
     110
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if
     continue
     
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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111. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     111
     111
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if
     continue
     
     (+1)
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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112. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     112
     112
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if
     continue
     
     (+1)
     (+2)
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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113. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     113
     113
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if
     continue
     
     (+1)
     (+2) (+1)
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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114. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     114
     114
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if continue
     (+1)
     (+2) (+1)
     ෳࡶ౓: 4
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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115. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     115
     115
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if
     continue
     
     (+1)
     (+2) (+1)
     ෳࡶ౓: 4
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     ࣮૷ͷࢀߟ: https://github.com/fzipp/gocyclo, https://github.com/uudashr/gocognit
     

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116. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     116
     116
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if
     continue
     
     (+1)
     (+2) (+1)
     ෳࡶ౓: 4
     ෳࡶ౓Λอ࣋
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     ࣮૷ͷࢀߟ: https://github.com/fzipp/gocyclo, https://github.com/uudashr/gocognit
     

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117. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     117
     117
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if
     continue
     
     (+1)
     (+2) (+1)
     ෳࡶ౓: 4
     ωετͷਂ͞Λอ࣋
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     ࣮૷ͷࢀߟ: https://github.com/fzipp/gocyclo, https://github.com/uudashr/gocognit
     

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118. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ
     ؔ਺ຖʹ Visitor Ͱ֤ϊʔυΛ૸ࠪͤ͞Δ
     118
     118
     FuncDecl
     CallExpr
     ForStmt
     ReturnStmt
     IfStmt BranchStmt
     ※ ؆ུ൛AST
     for
     if
     continue
     
     (+1)
     (+2) (+1)
     ෳࡶ౓: 4
     ࣮૷ͷࢀߟ: https://github.com/fzipp/gocyclo, https://github.com/uudashr/gocognit
     ܭࢉϧʔϧͷΤοδέʔε΁ͷରԠ
     (ࣗݾ࠶ؼͷݕ஌ ΍ʮelse if ͱ ifʯͷ۠ผ )
     ※ ݸผͷ࿩ͳͷͰؾʹ͠ͳͯ͘OK
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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119. ֤ϊʔυ΁ͷ૸ࠪॲཧͬͯͲ͏͢Ε͹
     119
     119
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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120. go/ast ʹؔ਺͕༻ҙ͞Ε͍ͯΔ
     120
     120
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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121. 3-3. ૸ࠪͷ࣮૷
     121
     121
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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122. ● ૸ࠪͷ࣮૷
     122
     122
     ast.Walk
     ࢦఆͨ͠ node ҎԼΛ visitor Ͱ૸ࠪ
     ast.Visitor
     ࢦఆ͞Εͨ node ΛVisitͰ૸ࠪ
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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123. ● ૸ࠪͷ࣮૷
     123
     123
     ast.Walk
     ࢦఆͨ͠ node ҎԼΛ visitor Ͱ૸ࠪ
     ast.Visitor
     ࢦఆ͞Εͨ node ΛVisitͰ૸ࠪ
     Visit ͷ࣮૷ྫ
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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124. ● ૸ࠪͷ࣮૷
     124
     124
     ast.Walk
     ࢦఆͨ͠ node ҎԼΛ visitor Ͱ૸ࠪ
     ast.Visitor
     ࢦఆ͞Εͨ node ΛVisitͰ૸ࠪ
     }Node͝ͱʹ
     ෼ذͯ͠ॲཧ
     Visit ͷ࣮૷ྫ
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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125. ● ૸ࠪͷ࣮૷
     125
     125
     ast.Walk
     ࢦఆͨ͠ node ҎԼΛ visitor Ͱ૸ࠪ
     ast.Visitor
     ࢦఆ͞Εͨ node ΛVisitͰ૸ࠪ
     }Node͝ͱʹ
     ෼ذͯ͠ॲཧ
     Visit ͷ࣮૷ྫ
     ͜͜ͷத਎͸ͲΜͳײ͡ʁ
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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126. ● ૸ࠪͷ࣮૷
     ྫ: ForStmt ༻ͷॲཧ
     126
     126
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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127. 1 + (ωετͷਂ͞)
     ͚ͩෳࡶ౓Λ௥Ճ
     ● ૸ࠪͷ࣮૷
     ྫ: ForStmt ༻ͷॲཧ
     127
     127
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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128. ● ૸ࠪͷ࣮૷
     ྫ: ForStmt ༻ͷॲཧ
     ॳظԽɾ৚݅ɾมԽʹཁૉ͕
     ͋Ε͹ͦͪΒΛ૸ࠪ
     (ਂ͞༏ઌ)
     128
     128
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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129. ● ૸ࠪͷ࣮૷
     ྫ: ForStmt ༻ͷॲཧ
     ωετΛ1ͭਂͯ͘͠ຊମॲཧ
     ↓
     ऴΘͬͨΒωετΛ1ͭ໭͢
     129
     129
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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130. ᶅ ֤ؔ਺಺ͷෳࡶ౓Λܭࢉ ׬ྃʂ
     130
     130
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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131. ᶃʙᶅΛ૊Έ߹ΘͤΔ
     131
     131
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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132. 132
     132
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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133. 133
     133
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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134. 134
     134
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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135. 135
     135
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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136. ׬੒඼͸ͪ͜Β
     https://github.com/nrnrk/gocognito
     136
     136
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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137. ײ૝
     137
     137
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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138. go/ast ศརʂָ͍͠ʂ
     138
     138
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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139. go/ast ศརʂָ͍͠ʂ
     139
     139
     5. ෳࡶ౓ܭଌπʔϧ࣮૷
     

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140. ֶͼͱิ଍
     140
     140
     

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141. ● ֶͼ
     ○ go/ast ͷߏ଄ମΛཧղ͢Δͱ͖ͷίπ
     ■ Stmt(จ) ͳͲͰ෼ྨ͢ΔͱΘ͔Γ΍͍͢
     ■ Goݴޠ࢓༷ͷϖʔδͰݕࡧͯ͠Θ͔Δ͜ͱ΋ʂ
     ■ tenntenn ͞Μͷهࣄ܈͸੩తղੳͷ޿͍ൣғΛղઆͯ͘͠Ε͍ͯΔ
     ○ ੩తղੳπʔϧͷࣗ࡞ʹΑͬͯ go/ast ͱ Goݴޠͷཧղ͕ਂ·ͬͨ
     ■ → ʮ੩తղੳπʔϧ͍ͭͰ΋࡞ΕΔͥʂʯͱੵۃతͳؾ࣋ͪʹ
     6. ֶͼͱิ଍
     141
     

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142. ● ิ଍
     ○ golang.org/x/tools/go/analysis Λ࢖͏ͱ΋ͬͱศརʂ
     ■ ࡞ͬͨπʔϧΛ؆୯ʹఏڙͰ͖Δ(Analyzer)
     ■ ͢Ͱʹ͋ΔπʔϧΛ؆୯ʹ૊Έ߹ΘͤΒΕΔ (FuncDecl ͷϑΟϧλ)
     ■ ςετ͕؆୯ʹ͔͚Δ(analysistest)
     ○ ͦͷଞͷؔ࿈ϥΠϒϥϦ
     ■ golang.org/x/tools/go/ssa
     ● ม਺ͷ࠶୅ೖͳͲΛ௥͍͔͚Δඞཁ͕͋Δͱ͖ͳͲ
     ■ golang.org/x/tools/go/ast/astutil
     ● AST ࣗମʹมߋΛՃ͑Δͱ͖ͳͲ
     142
     6. ֶͼͱิ଍
     

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143. ● ิ଍
     ○ golang.org/x/tools/go/analysis Λ࢖͏ͱ΋ͬͱศརʂ
     ■ ࡞ͬͨπʔϧΛ؆୯ʹఏڙͰ͖Δ(Analyzer)
     ■ ͢Ͱʹ͋ΔπʔϧΛ؆୯ʹ૊Έ߹ΘͤΒΕΔ (FuncDecl ͷϑΟϧλ)
     ■ ςετ͕؆୯ʹ͔͚Δ(analysistest)
     ○ ͦͷଞͷؔ࿈ϥΠϒϥϦ
     ■ golang.org/x/tools/go/ssa
     ● ม਺ͷ࠶୅ೖͳͲΛ௥͍͔͚Δඞཁ͕͋Δͱ͖ͳͲ
     ■ golang.org/x/tools/go/ast/astutil
     ● AST ࣗମʹมߋΛՃ͑Δͱ͖ͳͲ
     143
     6. ֶͼͱิ଍
     

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144. 144
     6. ֶͼͱิ଍
     golang.org/x/tools/go/analysis/analysistest ͷྫ
     → ςετର৅ͷؔ਺Λ testdata/src/a/a.go ʹஔ͍ͯɺ “// want “ ίϝϯτΛॻ͚ͩ͘Ͱྑ͍ʂ
     testdata/src/a/a.go
     

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145. 145
     6. ֶͼͱิ଍
     golang.org/x/tools/go/analysis/analysistest ͷྫ
     → ςετର৅ͷؔ਺Λ testdata/src/a/a.go ʹஔ͍ͯɺ “// want “ ίϝϯτΛॻ͚ͩ͘Ͱྑ͍ʂ
     testdata/src/a/a.go
     

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146. ·ͱΊ
     146
     146
     

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147. ● ·ͱΊ
     ○ Cognitive Complexity ͸ɺਓؒʹͱͬͯͷෳࡶ౓Λද͢ࢦඪ
     ○ go/ast Λ࢖͏͜ͱͰෳࡶ౓ͷܭଌπʔϧͳͲͷ੩తղੳπʔϧΛ؆୯ʹ࣮
     ૷͢Δ͜ͱ͕Ͱ͖Δ
     ■ golang.org/x/tools/go/analysis ͳͲ΋ศར
     ○ go/ast ָ͔ͬͨ͠ʂ࢖ͬͨ͜ͱ͕ͳ͍ਓ͸ੋඇ࢖ͬͯΈΑ͏ʂ
     147
     7. ·ͱΊ
     ͓͢͢Ί͍ͨ͠GoϥΠϒϥϦ౤ථड෇த!
     

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