Swiftda guard operatori

Swift dasturlash tilida guard operatori ma'lum shart bajarilmasa, dastur boshqaruvini scope'dan chiqarish uchun ishlatiladi.

guard operatori if operatoriga o'xshaydi, farqi shundaki:

if operatori shart bajarilganda ishlaydi
guard operatori shart bajarilmasa ishlaydi

Sintaksis:

guard expression else {
    // kod bloki
    // boshqaruv operatori: return, break, continue yoki throw
}

expression qiymati true bo'lsa → guard ichidagi kod bajarilmaydi
expression qiymati false bo'lsa → guard ichidagi kod bajariladi

guard blokidan chiqish uchun return, break, continue yoki throw ishlatilishi majbur.

guard operatori qanday ishlaydi?

shart tekshirildi → false → guard ichidagi kod bajarildi → boshqaruv operatori bilan scope'dan chiqildi

Misol:

Swift•

guard operatori - while loop

var i = 2

while (i <= 10) {
  
  // juft sonni tekshirish
  guard i % 2 == 0 else {
      i = i + 1
      continue
  }

  print(i)
  i = i + 1
}

Tushuntirish:

i % 2 == 0 false bo'lsa → guard ichidagi kod ishlaydi va continue bilan keyingi iteratsiyaga o'tadi
Faqat juft sonlar chop etiladi.

guard operatori funksiyada

Misol:

Swift•

guard operatori - toq/juft tekshirish

func checkOddEven(number: Int) {
  guard number % 2 == 0 else {
      print("\(number) is Odd Number")
      return
  }
  print("\(number) is Even Number")
}

// Toq son
checkOddEven(number: 23)

Tushuntirish:

number 23 → number % 2 == 0 false
guard ichidagi kod bajariladi → Odd Number chiqariladi

Endi number = 24 bo'lsa:

Swift•

guard operatori - juft son

func checkOddEven(number: Int) {
 
  guard number % 2 == 0 else {
      print("\(number) is Odd Number")
      return
  }

    print("\(number) is Even Number")
}

// Juft son  
checkOddEven(number: 24)

number juft bo'lgani uchun guard ichidagi kod o'tkazib yuboriladi, boshqa kod bajariladi.

guard bir nechta shartlar bilan

Misol:

Swift•

guard - bir nechta shartlar

func checkJobEligibility(age: Int) {

  guard age >= 18, age <= 40 else {
      print("Not Eligible for Job")
      return
  }

  print("You are eligible for this job")
}

checkJobEligibility(age: 33)

Shartlar vergul bilan ajratilgan
Barcha shartlar true bo'lsa → guard o'tkazib yuboriladi

guard let - Optional Unwrapping

Misol:

Swift•

guard let - optional unwrap

func checkAge(age: Int?) {

  guard let myAge = age else {
      print("Age is undefined")
      return
  }

  print("My age is \(myAge)")
}

checkAge(age: 22)

age qiymatga ega → guard-let ichidagi kod bajarilmaydi
Agar age = nil bo'lsa → "Age is undefined" chiqariladi

guard vs if

if operatori bilan:

Swift•

if operatori

func voteEligibility(age:Int) {


  if age >= 18 {
      print("Eligible to vote")
  } else {
      print("Not eligible to vote")
  }
}

voteEligibility(age:42)

guard operatori bilan:

Swift•

guard operatori

func voteEligibility(age: Int) {

  guard age >= 18 else {
      print("Not Eligible to vote")
      return
  }

  print("Eligible to vote")
}

voteEligibility(age: 42)

guard shart false bo'lsa → funksiyani darhol tark etadi
if operatorida esa else qismi ishlaydi

📚 Masalalarni qanday yechish kerak?

✅ Namuna: 1-masala yechimi

Masala: Son musbat bo'lsa sonning o'zini, aks holda 0 qaytaring. guard ishlatib yechiladi.

Bosqichma-bosqich yechim:

1-qadam: Masalani tushunish

n = 5 → musbat → 5 qaytaring
n = -3 → manfiy → 0 qaytaring
n = 0 → nol (musbat emas) → 0 qaytaring

2-qadam: guard bilan yechish

guard n > 0 else {
    return 0  // musbat bo'lmasa 0
}
return n  // musbat bo'lsa n

3-qadam: To'liq yechim

Swift•

1-masala yechimi

func solve(_ n: Int) -> Int {
  guard n > 0 else {
      return 0
  }
  return n
}

// Tekshirish
print(solve(5))    // 5
print(solve(-3))   // 0
print(solve(0))    // 0
print(solve(100))  // 100

Natija: Barcha testlar o'tadi ✅

Izoh:

guard n > 0 — n musbat ekanligini tekshiradi
Agar n > 0 false bo'lsa (ya'ni n ≤ 0) → else bloki ishlaydi → return 0
Agar n > 0 true bo'lsa → guard o'tkazib yuboriladi → return n
guard "early exit" pattern uchun juda qulay

if bilan solishtirish:
if n > 0 {
    return n
} else {
    return 0
}
guard kodni ixchamroq va o'qilishi oson qiladi.

Xulosa

guard — shart false bo'lsa scope'dan chiqish
if dan farqi: guard false holatga fokuslanadi
return, break, continue, throw — majburiy
guard let — optional unwrapping
Early exit — guard ning asosiy maqsadi
Bir nechta shartlarni vergul bilan ajrating