<script>
var length=100;
function A(){
alert(this.length);
}
function B(a){
this.length=10;
arguments[0]();
}
var b=new B(A);//10
</script>
<script>
var length=100;
function A(){
alert(this.length);
}
function B(a){
this.length=10;
arguments[0]();
}
var b=new B(A);//10
</script>