<html>
<head>
<meta charset="utf-8">
<title>symbol的内置属性</title>
</head>
<body>
<script type="text/javascript">
// class Person {
// static [Symbol.hasInstance](param){
// console.log(param)
// console.log('我被用来检测类型了...')
// return true
// }
// }
// let obj = {}
// console.log(obj instanceof Person)
let arr = [1,2,3]
let arr2 = [4,5,6]
arr2[Symbol.isConcatSpreadable] = false //只适用于concat
console.log(arr2.concat(arr))
console.log([...arr2,...arr])
</script>
</body>
</html>