isObject%26isFunction%26isWindow

笼统校验是否为对象

const isObject = function isObject(obj) {
  return obj !== null && /^(object|function)$/.test(typeof obj)
}

检测是否为函数

const isFunction = function isFunction(obj) {
  return typeof obj === 'function'
}

检测是否为window

const isWindow = function isWindow(obj) {
  return obj != null && obj === obj.window
}