Example1.swift

// Save item if not exist
let storingResult =  UserDefaults.safe.setValue("123456", forKey: "selected_number", forceOverride: { 
  return false
})
// return StoringResult.success

Example2.swift

// Don't override if there is a value exist
let storingResult =  UserDefaults.safe.setValue("123456", forKey: "selected_number", forceOverride: { 
  return false
})
// return StoringResult.discarded

Example3.swift

let role = Role.admin
// Force override set to true due a condition
let storingResult = UserDefaults.safe.setValue("123456", forKey: "selected_number", forceOverride: {
return role == .admin
})
// return StoringResult.overrided