MutatingFunction.swift

import Foundation

// Mutating function
// The properties of value types cannot be modified within its instance methods by default.

struct User {
    var name : String
    var age : Int
    var address : String
    
    mutating func updateName(_ newName: String) {
        self.name = newName
    }
}

let user = User(name: "ajay", age: 12, address: "pune")
user.updateName("rahul")