if let and guard let Binding
Safe optional unwrapping with conditional and early-exit binding patterns.
Welcome
Optionals represent values that may or may not exist. Safe unwrapping with `if let` and `guard let` is the foundation of crash-free Swift code.
What is an Optional?
```swift
var name: String? = "Alice" // has a value
var age: Int? = nil // no value
```
An Optional wraps a value in `.some(value)` or `.none`. You must unwrap it before use.