Nil Coalescing - Swift Programming

The ?? operator provides a fallback value when an optional is nil.

Choose a fallback

nil_coalescing.swift

let preferredName: String? = 
let fallbackName = "Guest"
let displayName = preferredName ?? fallbackName

print("displayName=\(displayName)")

let preferredName: String? = 
let fallbackName = "Guest"
let displayName = preferredName ?? fallbackName

print("displayName=\(displayName)")

let preferredName: String? = 
let fallbackName = "Guest"
let displayName = preferredName ?? fallbackName

print("displayName=\(displayName)")

fallback Nil coalescing keeps fallback logic compact. If the optional has a value, Swift uses it; otherwise Swift uses the value on the right side of `??`.