こんなTypeScriptはいやだ！ / I hate this kind of TypeScript!

登壇者名：佐藤 拓人
登壇したイベント：TSKaigi 2024（https://tskaigi.org）
登壇したイベントタイトル：こんなTypeScriptはいやだ！

登壇したイベントの登壇者URL：https://tskaigi.org/talks/takuuuuuuu777

Transcript

1. Copyright © 2023 Bitkey Inc. All right reserved. ͜ΜͳTypeScript͸͍΍ͩʂ גࣜձࣾϏοτΩʔɹࠤ౻ ୓ਓɹ2024/05/11
2. Copyright © 2023 Bitkey Inc. All right reserved. 2 ࣗݾ঺հ ࠤ౻ ୓ਓ Sato Takuto 2015.04 2019.05 2020.01 େֶ(ݐஙֶઐ߈)ଔۀޙɺ גࣜձࣾϫʔΫεΞϓϦέʔγϣϯζʹೖࣾ ձܭγεςϜͷιϑτ΢ΣΞ։ൃΛ୲౰ ಛʹࡒ຿ձܭͷ࢓༁ؔ࿈ ϏοτΩʔ΁ࢀը ECαΠτͷ։ൃ / อकɺࣾ಺γεςϜͷ։ൃ TaKuTyͷ։ൃ ࠓͷHomeࣄۀͷલ਎ͱͳΔResidenceνʔϜʹ഑ଐ bitlockΛѻ͏؅ཧը໘΍όοΫΤϯυɺappͷ։ൃʹै ࣄ Now HomeϓϩμΫτͷٕज़੹೚ऀ ෳࡶͳࣄ৅ΛಡΈղ͍ͯߏ଄Խ͠ɺந৅Խ / ൚༻ԽͰ ͖ΔΑ͏ʹઃܭ͠ɺ௿ίετͰଟ͘ͷՁ஋ΛͩͤΔ։ ൃΛ͢Δ͜ͱΛ޷Ή
3. Copyright © 2023 Bitkey Inc. All right reserved. 3 ࣗݾ঺հ ςΫϊϩδʔͷྗͰ͋ΒΏΔ΋ͷΛ ҆શͰ ศརͰ ؾ࣋ͪΑ͘ʮͭͳ͛Δʯ εϚʔτϩοΫͳͲΛ༻͍ͯ ϦΞϧͱσδλϧͷ෼அΛղফ
4. Copyright © 2023 Bitkey Inc. All right reserved. 4 TypeScrips޷͖Ͱ͔͢ʁ 1. ͸͡Ίʹ
5. Copyright © 2023 Bitkey Inc. All right reserved. 5 1. ͸͡Ίʹ (޷͖Ͱ΋ɺݏ͍Ͱ΋...) TypeScriptͰ͜Μͳ࣮૷͸ݏͩͳ ͬͯࢥͬͨ͜ͱ͕͋Δํ͸ ଟ͍ͷͰ͸ͳ͍Ͱ͠ΐ͏͔ʁ
6. Copyright © 2023 Bitkey Inc. All right reserved. 6 ࣮ࡍʹݱ৔Ͱײͨ͡ ͜ΜͳTypeScript͸ݏͩࣄྫ ͜ΕΛ๷͙ରԠࡦ 1. ͸͡Ίʹ
7. Copyright © 2023 Bitkey Inc. All right reserved. 7 ϒʔε΍͍ͬͯ·͢ʂ 1. ͸͡Ίʹ
8. Copyright © 2023 Bitkey Inc. All right reserved. 8 1. ੈք͕ ”any” ͰᷓΕ͍ͯΔ
9. Copyright © 2023 Bitkey Inc. All right reserved. 9
10. Copyright © 2023 Bitkey Inc. All right reserved. 10
11. Copyright © 2023 Bitkey Inc. All right reserved. 11
12. Copyright © 2023 Bitkey Inc. All right reserved. 12 1. ͸͡Ίʹ
13. Copyright © 2023 Bitkey Inc. All right reserved. 13 ʮͳʹ͔ʯͬͯͳʹʁ 1. ੈք͕ ”any” ͰᷓΕ͍ͯΔ
14. Copyright © 2023 Bitkey Inc. All right reserved. 14 Bad Point ɾίʔυ͕આ໌੹೚Λ์غ͍ͯ͠Δ ɾνʔϜ։ൃ͢Δؾͳ͠...ͱࢥΘΕ͏Δ ɾAIͷαϙʔτ΋ड͚ͮΒ͘ͳΔ 1. ੈք͕ ”any” ͰᷓΕ͍ͯΔ
15. Copyright © 2023 Bitkey Inc. All right reserved. 15 How to Improvement 1. ੈք͕ ”any” ͰᷓΕ͍ͯΔ ɾnoImplicitAny:true (tsconfig.json) ɾίʔυ͕આ໌੹೚ΛՌ͔ͨ͢ؾֻ͔͚Δ (1೥ޙͷࣗ෼͕ཧղ/อकՄೳ͔) ɾϞϒϓϩ / ϖΞϓϩ Λੵۃ࣮ࢪ
16. Copyright © 2023 Bitkey Inc. All right reserved. 16 TypeScriptΛ࢖ͬͯ ʮΘ͔Δʯঢ়ଶʹ͠Α͏ʂ 1. ੈք͕ ”any” ͰᷓΕ͍ͯΔ
17. Copyright © 2023 Bitkey Inc. All right reserved. 17 2. ֎ք͔Β͘Δʮ஋ʯ͕ʮܕʯͱဃ཭͍ͯ͠Δ
18. Copyright © 2023 Bitkey Inc. All right reserved. 18 2. ֎ք͔Β͘Δʮ஋ʯ͕ʮܕʯͱဃ཭͍ͯ͠Δ ɾAPIͷݺͼग़͢ॲཧɺAPIͷఆٛɺDBͷࢀরͳͲ...
19. Copyright © 2023 Bitkey Inc. All right reserved. 19 2. ֎ք͔Β͘Δʮ஋ʯ͕ʮܕʯͱဃ཭͍ͯ͠Δ ɾAPIͷݺͼग़͢ॲཧɺAPIͷఆٛɺDBͷࢀরͳͲ... ඞਢ߲໨ʁ ଞͷ߲໨͸ͳ͍ʁ ඞͣStringܕʁ
20. Copyright © 2023 Bitkey Inc. All right reserved. 20 ܕΛ৴͡ΒΕͳ͚Ε͹ ͳʹΛ৴͡Ε͹ྑ͍ʂʁ 2. ֎ք͔Β͘Δʮ஋ʯ͕ʮܕʯͱဃ཭͍ͯ͠Δ
21. Copyright © 2023 Bitkey Inc. All right reserved. 21 Bad Point ɾී௨ʹ࣮૷͍ͯͨ͠ΒόάΔ ɾٙ৺҉َʹͳΔ ɾ͍Ζ͍Ζؾʹͩͯ͠͠มߋͰ͖ͳ͘ͳΔ 2. ֎ք͔Β͘Δʮ஋ʯ͕ʮܕʯͱဃ཭͍ͯ͠Δ
22. Copyright © 2023 Bitkey Inc. All right reserved. 22 ɾ֎քͱͷڥքͰνΣοΫ͢Δ ɾఆ͔ٛΒࣗಈੜ੒͢ΔπʔϧΛར༻͢Δ (PrismaͳͲ) How to Improvement 2. ֎ք͔Β͘Δʮ஋ʯ͕ʮܕʯͱဃ཭͍ͯ͠Δ
23. Copyright © 2023 Bitkey Inc. All right reserved. 23 ܕΛ৴པͰ͖Δঢ়ଶʹ͠Α͏ʂ 2. ֎ք͔Β͘Δʮ஋ʯ͕ʮܕʯͱဃ཭͍ͯ͠Δ
24. Copyright © 2023 Bitkey Inc. All right reserved. 24 3. ഑ྻͷཁૉͷundefinedߟྀ
25. Copyright © 2023 Bitkey Inc. All right reserved. 25 3. ഑ྻͷཁૉͷundefinedߟྀ
26. Copyright © 2023 Bitkey Inc. All right reserved. 26 3. ഑ྻͷཁૉͷundefinedߟྀ undefined͕ߟྀ͞ Εͳ͍
27. Copyright © 2023 Bitkey Inc. All right reserved. 27 ͜Εͬͯຊ౰ʹେৎ෉ʁ 4. ഑ྻͷཁૉͷundefinedߟྀ
28. Copyright © 2023 Bitkey Inc. All right reserved. 28 Bad Point ɾTypeScriptʹ਎Λ೚ͤΔ͜ͱ͕Ͱ͖ͳ͍ ɾৗʹέΞ͠ଓ͚ͳ͚Ε͹ͳΒͳ͍ 4. ഑ྻͷཁૉͷundefinedߟྀ
29. Copyright © 2023 Bitkey Inc. All right reserved. 29 ɾnoUncheckedIndexedAccess:true (tsconfig.json) How to Improvement 4. ഑ྻͷཁૉͷundefinedߟྀ
30. Copyright © 2023 Bitkey Inc. All right reserved. 30 ҙਤͤ͵ϛεΛࣄલʹ௵ͦ͏ʂ 4. ഑ྻͷཁૉͷundefinedߟྀ
31. Copyright © 2023 Bitkey Inc. All right reserved. 31 4. ྻڍܕͷ௥Ճʹ௥ैͰ͖ͳ͍
32. Copyright © 2023 Bitkey Inc. All right reserved. 32 4. ྻڍܕͷ௥Ճʹ௥ैͰ͖ͳ͍ ɾbefore ɾafter
33. Copyright © 2023 Bitkey Inc. All right reserved. 33 Ͳ͕͜मਖ਼ඞཁ͔ߟ͑ͳ͖Ό... 4. ྻڍܕͷ௥Ճʹ௥ैͰ͖ͳ͍
34. Copyright © 2023 Bitkey Inc. All right reserved. 34 Bad Point ɾमਖ਼͕ඞཁͳՕॴΛػցతʹચ͍ग़͢͜ͱ͕ Ͱ͖ͳ͍ 4. ྻڍܕͷ௥Ճʹ௥ैͰ͖ͳ͍
35. Copyright © 2023 Bitkey Inc. All right reserved. 35 Bad Point ɾswitchจͰneverΛར༻͢Δ ɾswitch-exhaustiveness-checkΛར༻ 4. ྻڍܕͷ௥Ճʹ௥ैͰ͖ͳ͍
36. Copyright © 2023 Bitkey Inc. All right reserved. 36 TypeScriptͱ͏·͘෇͖߹ͬͯ อक͠΍͘͢͠Α͏ʂ 4. ྻڍܕͷ௥Ճʹ௥ैͰ͖ͳ͍
37. Copyright © 2023 Bitkey Inc. All right reserved. 37 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ
38. Copyright © 2023 Bitkey Inc. All right reserved. 38 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ ΈΜͳେ޷͖ Prisma
39. Copyright © 2023 Bitkey Inc. All right reserved. 39 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ ΈΜͳେ޷͖ Prisma include۠ͷࢦఆʹج͍ͮͯ औಘ͞ΕΔ஋ʹ΋ ಈతʹܕ͕෇༩͞ΕΔ
40. Copyright © 2023 Bitkey Inc. All right reserved. 40 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ ΈΜͳେ޷͖ Prisma include۠ͷࢦఆʹج͍ͮͯ औಘ͞ΕΔ஋ʹ΋ ಈతʹܕ͕෇༩͞ΕΔ ܕͱͯ͠΋࣮ଶͱͯ͠΋ ஋͕औಘ͞ΕΔ ܕͱͯ͠΋࣮ଶͱͯ͠΋ ஋͕औಘ͞Εͳ͍
41. Copyright © 2023 Bitkey Inc. All right reserved. 41 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ Include۟Λ੾Γग़͠
42. Copyright © 2023 Bitkey Inc. All right reserved. 42 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ Include۟Λ੾Γग़͠ trueͰ͸ͳ͘booleanѻ͍ͱͳΔ
43. Copyright © 2023 Bitkey Inc. All right reserved. 43 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ Include۟Λ੾Γग़͠ trueͰ͸ͳ͘booleanѻ͍ͱͳΔ include͕۟booleanѻ͍ͷͨΊ औಘ͞ΕΔ͔ະ֬ఆͷѻ͍ͱͳΔ
44. Copyright © 2023 Bitkey Inc. All right reserved. 44 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ as const Λར༻
45. Copyright © 2023 Bitkey Inc. All right reserved. 45 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ as const Λར༻ as const ͷΈͩͱ true͸ҡ࣋͞ΕΔ͕ த਎ʹޡΓ͕͋ͬͯ΋͜͜Ͱ͸ؾ෇͚ͳ͍...
46. Copyright © 2023 Bitkey Inc. All right reserved. 46 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ ར༻͢ΔՕॴͰ औಘͰ͖͍ͯͳ͍͜ͱʹؾͮ͘ as const Λར༻ as const ͷΈͩͱ true͸ҡ࣋͞ΕΔ͕ த਎ʹޡΓ͕͋ͬͯ΋͜͜Ͱ͸ؾ෇͚ͳ͍...
47. Copyright © 2023 Bitkey Inc. All right reserved. 47 ɾ࣮૷ϛε࣌ʹɺϛεपลͰؾ෇͚ͳ͍ ɾ໰୊ͷݕ஌͕஗Εɺ໰୊ͷղফ͕൥ࡶʹ Bad Point 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ
48. Copyright © 2023 Bitkey Inc. All right reserved. 48 ɾsatisfiesΛ༻͍Δ How to Improvement 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ
49. Copyright © 2023 Bitkey Inc. All right reserved. 49 ɾsatisfiesΛ༻͍Δ How to Improvement trueѻ͍Ͱܕ͕౉͞ΕΔͷͰ ܕͱͯ͠΋औಘ͞ΕΔલఏͱͳΔ 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ
50. Copyright © 2023 Bitkey Inc. All right reserved. 50 ɾsatisfiesΛ༻͍Δ How to Improvement ࢦఆͷ࢓ํʹޡΓ͕͋Ε͹ଈ࣌ʹؾ͚ͮͯ ิ׬ͷαϙʔτΛड͚ͳ͕Βमਖ਼Ͱ͖Δ trueѻ͍Ͱܕ͕౉͞ΕΔͷͰ ܕͱͯ͠΋औಘ͞ΕΔલఏͱͳΔ 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ
51. Copyright © 2023 Bitkey Inc. All right reserved. 51 ܕͷ࢓૊ΈΛ্ख͘࢖ͬͯ ΑΓ؆୯ʹ࣮૷Ͱ͖Δ޻෉Λʂ 4. ܕͷύλʔϯͱ۩ମతͳ஋ͱͷڱؒ
52. Copyright © 2023 Bitkey Inc. All right reserved. 52 5. ͓·͚
53. Copyright © 2023 Bitkey Inc. All right reserved. 53 օ͞Μ͔Βͷҙݟ͕ ͜Μͳʹू·Γ·ͨ͠ʂ 5. ͓·͚
54. Copyright © 2023 Bitkey Inc. All right reserved. 54 XϑΥϩʔͥͻ͓Ͷ͕͍͠·͢ʂ 5. ͓·͚
55. End of File Copyright © 2023 Bitkey Inc. All right reserved. 55