08-cb问题

<script type="text/javascript">
	
	var name='hello';
	var id=2;
	function fun1(cb) {
		setTimeout(function() {
			cb(name);//固定了
		},1000);
	}
	fun1(
		function(a,b) {
	    	        console.log(a)//hello
			console.log(b)//undefined
			console.log(arguments.length);
		}
	);
		
</script>