javascript - Why is arguments.callee.caller.name undefined? - Stack Overflow

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How e this doesn't alert "http://127.0.0.1/sendRequest"? (Available at /)

var foo = {
    sendRequest: function() {
        alert(bar.getUrl());
    }
};                    

var bar = {
    getUrl: function() {
        return 'http://127.0.0.1/' + arguments.callee.caller.name;
    }
};

foo.sendRequest();

How e this doesn't alert "http://127.0.0.1/sendRequest"? (Available at http://jsfiddle/Gq8Wd/52/)

var foo = {
    sendRequest: function() {
        alert(bar.getUrl());
    }
};                    

var bar = {
    getUrl: function() {
        return 'http://127.0.0.1/' + arguments.callee.caller.name;
    }
};

foo.sendRequest();

• javascript
• arguments

Share Improve this question Follow edited Nov 3, 2011 at 17:48 Trump Voters Deserve Damnation 130k8888 gold badges358358 silver badges381381 bronze badges asked Nov 3, 2011 at 17:44 user979672user979672 1,84333 gold badges2323 silver badges3232 bronze badges 3

• what you try to acheive ??????????? – Qchmqs Commented Nov 3, 2011 at 17:46
• 1 Because you have no function with name sendRequest, only anonymous functions. – Felix Kling Commented Nov 3, 2011 at 17:46
• 3 Even if callee and caller e in quite handy sometimes, those are deprecated since ES5-strict. So I'd remend not to use them anymore. – jAndy Commented Nov 3, 2011 at 17:49

Add a ment  | 

4 Answers 4

Sorted by: Reset to default 2

Putting a value in an object literal, as you're doing, doesn't affect the value at all.

var foo = {
    sendRequest: ...

The function value is only affected by the function expression, which doesn't contain a name.

             ... function() {
        alert(bar.getUrl());
    }

You need to include the name you want in the function expression itself ^[fiddle].

var foo = {
    sendRequest: function sendRequest() {

If you do this:

var foo = {
    sendRequest: function() {
        alert(bar.getUrl());
    }
};                    

var bar = {
    getUrl: function() {
        return  arguments.callee;
    }
};

foo.sendRequest();

You will notice that the function doesn't have name which is true:

function() {

This is anonymous function.

You can name you method : sendRequest: function myMethodName() {

Although the function is stored under the object property foo.sendRequest, and thus can be invoked via foo.sendRequest(), that function itself doesn't actually have a name. That's why arguments.callee.caller.name is empty.

Because the function that is calling the function being called is an anonymous function (and hence, has no name).

Try:

function sendRequest() {
    alert(bar.getUrl());
}

var foo = {
    sendRequest: sendRequest
};                    

var bar = {
    getUrl: function() {
        return 'http://127.0.0.1/' + arguments.callee.caller.name;
    }
};

foo.sendRequest();

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