JS arguments对象和call方法

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<script type="text/javascript">//<![CDATA[
function classA() {
    this.name='bluedestiny';
    this.show = function () {
        alert(this.name);
    }
}
function classB() {
    this.name = 'never-online';
}

var objA = new classA();
var objB = new classB();

objA.show.call(objB);
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