deepClone include prop of date, regexp etc.

deepClone.txt

function deepClone(obj) {
  function getType(obj) {
    return Object.prototype.toString.call(obj).replace(/^\[object (.+)\]$/, '$1').toLowerCase();
  }

  const type = getType(obj)
  if (!obj || typeof obj !== 'object') {
    return obj
  }

  // Dom Node
  if (obj.nodeType && 'cloneNode' in obj) {
    return obj.cloneNode(true);
  }

	// Date
	if (type === 'date') {
		const timestamp = obj.getTime()
		return new Date(timestamp)
	}

	// RegExp
	if (type === 'regexp') {
		const flags = [];
		if (obj.multiline) {
			flags.push('m')
		}
		if (obj.ignoreCase ) {
			flags.push('i')
		}
		if (obj.global) {
			flags.push('g')
		}
		return new RegExp(obj.source, flags.join(''))
	}

  let result = type === 'array' ? [] :
                  obj.constructor ? new obj.constructor() : {}

  for (const prop in obj) {
    if (obj.hasOwnProperty(prop)) {
      result[prop] = deepClone(obj[prop])
    }
  }

  return result;
}