TypeScript リテラル型について

Webナイト宮崎 Vol.10　～てげTypeScriptを学びたい～ - connpass https://tegehoge.connpass.com/event/186724/

Transcript

1. KOSUKE OGAWA 2020
   WebφΠτٶ࡚ No. 10
   Ϧςϥϧܕʹ͍ͭͯ
   

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2. ࣗݾ঺հ
   w 0HBXB,PTVLFʢ!LPPHBXBʣ
   w Ξϧגࣜձࣾʢ౦ژʣ
   w ٶ࡚͔ΒϑϧϦϞʔτ
   w J04 4XJGU
   "OESPJE ,PUMJO
   5ZQF4DSJQU $44 7VFKT /VYUKTͳͲ
   w ࠷ۙ͸ϑϩϯτΤϯυ͕ϝΠϯ
   

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3. ͋Δ೔
   ͱ͋ΔίʔυΛಡΜͰ͍ͨΒɺ
   ͜ΜͳίʔυΛݟ͚ͭͨ
   

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4. w AAͱ͔AAͱ͍͏ܕ͕͋Δʂʁ
   w BOVNCFSͳΒΘ͔Δ
   

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5. • 6 ΍ 2000 ͔͠ڐ͞Εͳ͍ܕ
   • จࣈྻͷϦςϥϧܕ΋͋Δ
   • const b: 'bar' = 'foo'; // Τϥʔ: Type '"foo"' is not assignable to type ‘"bar"'.
   Ϧςϥϧܕͱ͍͏Β͍͠
   

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6. • จࣈྻͷϦςϥϧܕΛ࣋ͭ஋͸stringܕͱͯ͠ѻ͏͜ͱ͕Ͱ͖Δ
   จࣈྻͷϦςϥϧܕ
   

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7. • ܕ஫ऍΛলུͯ͠΋ͪΌΜͱਪ࿦͞ΕΔ
   Ϧςϥϧܕͱܕਪ࿦
   

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8. ࢖͍ಓ
   

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9. • ϝϯόม਺ͷ஋Λมߋͯ͠΄͘͠ͳ͍ͱ͖
   ࢖͍ಓ1
   

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10. • ϢχΦϯܕͰ݁߹͢Δ
    ࢖͍ಓ2
    

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11. ͋Γ͕ͱ͏͍͟͝·ͨ͠
    

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