CodeToLive

Variables & Constants in Swift

Swift provides two ways to store values: variables (var) and constants (let).

Variables (var)

var score = 10
score = 20  // Valid
var name: String = "Alice"  // Explicit type

Constants (let)

let pi = 3.14159
// pi = 3.14  // Error: Cannot assign to let

Type Inference

let message = "Hello"  // Inferred as String
let count = 42        // Inferred as Int
let average = 3.14    // Inferred as Double

Optionals

var optionalName: String? = "Alice"
optionalName = nil

// Unwrapping
if let name = optionalName {
    print("Hello, \(name)")
}

Type Aliases

typealias AudioSample = UInt16
var maxAmplitude: AudioSample = 32767

Common Types

Type	Example
Int	42
Double	3.14159
String	"Hello"
Bool	true, false

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