Deep Cloning JavaScript Objects

deepClone.js

function deepClone(obj){
  // in case of premitives
  if(obj===null || typeof obj !== "object"){
    return obj;
  }
 
  // handle date objects
  if(obj instanceof Date){
    return new Date(obj.getTime());
  }
 
  // handle Array
  if(Array.isArray(obj)){
    var clonedArr = [];
    obj.forEach(function(element){
      clonedArr.push(deepClone(element));
    });
    return clonedArr;
  }
 
  // lastly, handle objects
  let clonedObj = new obj.constructor();
  for(var prop in obj){
    if(obj.hasOwnProperty(prop)){
      clonedObj[prop] = deepClone(obj[prop]);
    }
  }
  return clonedObj;
}

var newObj  = {
  name: "Paddy", 
  address: {
    town: "Lerum", 
    country: "Sweden"
  }
};

var newArr = [ [ {a: 'b'} ], [ {c: 'd'} ], [ {1: '2'} ] ];

deepClone(newObj);
deepClone(newArr);

// Other shallow cloning methods --

// for ES6 Object.assign:
// Object.assign({}, newObj);

// for JSON:
// JSON.parse(JSON.stringify(newObj))