Bool 값과 표현식

Bool 형식

let isLoggedIn = true
let hasError = false
print(isLoggedIn)
print(hasError)

비교로 불리언 만들기

let age = 20
let isAdult = age >= 18
let isTeen = age < 13
print(isAdult)
print(isTeen)

NOT 연산자

let isOnline = false
print(!isOnline)
let isOffline = !isOnline
print(isOffline)

AND 연산자

let hasTicket = true
let hasID = true
let canEnter = hasTicket && hasID
print(canEnter)

OR 연산자

let isWeekend = false
let isHoliday = true
let canRelax = isWeekend || isHoliday
print(canRelax)

표현식 결합하기

let temp = 22
let isComfortable = temp >= 18 && temp <= 26
print(isComfortable)

괄호 사용하기

let isAdmin = false
let isOwner = true
let isActive = true
let canEdit = (isAdmin || isOwner) && isActive
print(canEdit)

단락 평가

func check() -> Bool {
    print("check ran")
    return true
}
let result = false && check()
print(result)

if 문에서 불리언 사용하기

let isReady = true
if isReady {
    print("Go")
} else {
    print("Wait")
}

논리 결과 저장하기

let score = 85
let attempts = 2
let passed = score >= 60 && attempts <= 3
if passed {
    print("Passed")
}

불리언 동등성

let expected = true
let actual = (10 > 5)
print(expected == actual)
print(expected != actual)

빠른 확인

복습: 불리언 표현식

let inStock = true
let onSale = false
let shouldBuy = inStock && (onSale || true)
print(shouldBuy)