Learn Swift

Swift Topics

Click on a topic to expand and learn in detail.

• 1. Introduction to Swift

print("Hello, Swift!")
      

Swift is a modern, fast, and safe language used for developing Apple apps.

• 2. Variables & Constants

var age = 25          // variable
let name = "Alice"    // constant
let pi: Double = 3.14 // type annotation
      

Use var for changeable values, let for constants.

• 3. Operators

// Arithmetic
let sum = 5 + 3

// Comparison
let isAdult = age >= 18

// Logical
let flag = isAdult && true
      

Operators perform calculations, comparisons, and logic operations.

• 4. Conditions

if age >= 18 {
    print("Adult")
} else {
    print("Minor")
}

// Switch
switch age {
case 18:
    print("Exactly 18")
default:
    print("Other age")
}
      

Use if-else or switch to control program flow.

• 5. Loops

// for loop
for i in 0..<5 {
    print(i)
}

// while loop
var j = 0
while j < 5 {
    print(j)
    j += 1
}

// repeat-while
var k = 0
repeat {
    print(k)
    k += 1
} while k < 5
      

Loops allow repeating code multiple times.

• 6. Functions

func add(a: Int, b: Int) -> Int {
    return a + b
}
print(add(a: 5, b: 3))
      

Functions are reusable code blocks that can return values.

• 7. Object-Oriented Programming

class Person {
    var name: String
    var age: Int

    init(name: String, age: Int) {
        self.name = name
        self.age = age
    }

    func greet() {
        print("Hello \(name)")
    }
}

let p = Person(name: "Alice", age: 25)
p.greet()
      

Swift supports classes, objects, inheritance, encapsulation, and polymorphism.

• 8. Advanced Swift
• Protocols & Delegates
• Closures (Anonymous Functions)
• Optionals & Nil Handling
• Generics
• Error Handling (try-catch)

// Optional Example
var name: String? = "Alice"
print(name ?? "No Name")

// Closure
let square = { (x: Int) -> Int in x * x }
print(square(5))