2-2 instanceof

<script>
    var date = new Date();
    var arr = new Array();
    var obj = new Object();
    function MadeCat() {
        this.cat = '白猫';
    }
    var cat = new MadeCat();
    // 1. 对象的归属,对象由哪个构造器new出来的 
    console.log(date instanceof Date); // 
    console.log(arr instanceof Array); // 
    console.log(date instanceof Array); // 
    // 2. 一切皆对象,对象是他们祖先
    console.log('----', date instanceof Object); //
    console.log('----', arr instanceof Object); //
    console.log('----', obj instanceof Object); //
</script>