Unwrapping With If Let

To safely access the value inside an optional, we use if let — a technique called optional binding. This checks if the optional contains a value and, if so, unwraps it into a temporary constant.

var username: String? = "Swift_Dev"

if let name = username {
    print("Welcome, \(name)")
} else {
    print("No username found")
}
// Welcome, Swift_Dev

Here, if let checks whether username has a value. Since it does, the value is unwrapped into name, which exists only inside the if block. If username were nil, the else block would run instead.

var age: Int? = nil

if let unwrappedAge = age {
    print("Age is \(unwrappedAge)")
} else {
    print("Age not provided")
}
// Age not provided

Since age is nil, the condition fails and the else block executes. This prevents crashes that would occur if we tried to use a missing value directly.