Swift Tutorial 1

1. Swift Tutorial - 1
Jintin

2. Feature
• Modern
• Static Language
• Type Safety & Inference
• Objective-C Compatible
• Open Source

3. Hello World
print(“Hello, world”)

4. Const vs Variable
var a = 1
a = 2
let b = 1
b = 2 // error

5. Type Safe
var a: Int = 1
var b: Double = 1.1
var c: [Int] = [1, 2, 3]
var d: String = “hello”
var e: Int = 1.1 // error

6. Type Inference
var a: Int = 1
var b = 1 // b is Int too

7. Optional
var a: Int = nil // error
var b: Int? = nil

8. Optional
var a: Int = 1
print(a) // 1
var b: Int? = 1
print(b) // Optional(1)

9. Unwrapped Optional
var b: Int? = 1
print(b) // Optional(1)
print(b!) // 1

10. Control Flow: if
if a == 1 {
print(“a = 1”)
} else {
// do something
}

11. Control Flow: if let
var a: Int? = 1
if let b = a {
print(b)
}

12. Exercise
// print “Hello, [name]” if
name not nil, else print
“Hello there.”
var name: String?