'use strict';

var _isTouchScreen;

/**
 * 判断是否为触摸屏
 * @returns
 */
function isTouchScreen() {
  if (_isTouchScreen === undefined) {
    _isTouchScreen = 'ontouchstart' in window || window.DocumentTouch && document instanceof window.DocumentTouch;
  }

  return _isTouchScreen;
}

module.exports = isTouchScreen;
