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[iOS / Swift] Optional์ด๋ž€?

Optional์ด๋ž€?Optional์€ ๋ณ€์ˆ˜์— ๊ฐ’์ด ์žˆ์„ ์ˆ˜๋„ ์žˆ๊ณ  ์—†์„ ์ˆ˜๋„(nil) ์žˆ๋‹ค๋Š” ๊ฑธ ๋‚˜ํƒ€๋‚ด๋Š” ํƒ€์ž…์ด์—์š”.์ฆ‰, “์ด ๋ณ€์ˆ˜๋Š” ์•„์ง ๊ฐ’์ด ์—†์„ ์ˆ˜๋„ ์žˆ๋‹ค”๋Š” ๊ฑธ Swift์—๊ฒŒ ๋ฏธ๋ฆฌ ์•Œ๋ ค์ฃผ๋Š” ๊ฑฐ์ฃ .์ด๋ ‡๊ฒŒ nil์„ ๋Œ€์ž…ํ•˜๋ ค๊ณ  ํ•ด๋ฉด ์—๋Ÿฌ๊ฐ€ ๋ฐœ์ƒํ•˜๋Š”๋ฐ์š”. var name: String? = nilname = "์˜๋Œ์ฟค"์ด๋•Œ ?๋ฅผ ๋ถ™์—ฌ ์„ ์–ธํ•ด์•ผ nil์„ ์ €์žฅํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค.์ €๋Š” ์ฒ˜์Œ ์˜ต์…”๋„์„ ๋ฐฐ์šธ ๋•Œ ์Šˆ๋ขฐ๋”ฉ๊ฑฐ์˜ ๊ณ ์–‘์ด๋ผ๋Š” ๋น„์œ ๋ฅผ ๋“ค์—ˆ๋Š”๋ฐ ๊ณต๊ฐ์ด ๊ฐ€๋”๋ผ๊ตฌ์š”. ๊ทธ๋Ÿฐ๋ฐ ์ด๊ฑธ ๊ทธ๋ƒฅ print ํ•˜๋ฉด ์•„๋ž˜์ฒ˜๋Ÿผ ๋‚˜์˜ต๋‹ˆ๋‹ค.Optional("์˜๋Œ์ฟค")์ด๋Œ€๋กœ๋Š” ์“ธ ์ˆ˜ ์—†๊ฒ ์ฃ ! ๊ทธ๋ž˜์„œ ์˜ต์…”๋„์€ ‘๊ฐ’์„ ๊บผ๋‚ด๋Š” ๊ณผ์ •(์–ธ๋ž˜ํ•‘)’์ด ๊ผญ ํ•„์š”ํ•ฉ๋‹ˆ๋‹ค. 1. ๊ฐ•์ œ ์–ธ๋ž˜ํ•‘ (Forced Unwrapping)var name: String? =..

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