Object and function in JavaScript

Question

I am looking for a shorter way to make a JavaScript object that can be used as a function. For instance, I can do the following:

var A=function(){window.alert('Hello World');}
A.hello='World';

Notice that I can call A() or access A.hello.

Is there a way to accomplish this using curly braces to create the object?

var A={
    ?:function(){window.alert('Hello World');},
    hello:'World',
};

No, only functions can be used as functions (are callable). But as functions are objects as well you can easily assign properties to them. — Felix Kling
– Felix Kling, Commented Feb 15, 2012 at 1:29
If you just want shorter you can omit the var statement and say function A() ... with effectively the same result. But as per am not i am's answer there isn't a syntax to create a function and give it properties all in one statement. — nnnnnn
– nnnnnn, Commented Feb 15, 2012 at 1:34
Whats its the point? I mean if you replace ? by $ you easy could do A.$() and get the result with only two extra characters, what do you want to get? — ncubica
– ncubica, Commented Feb 15, 2012 at 1:45

m90 · Accepted Answer · 2013-09-03 14:06:54Z

3

As you know a function is an Object. Nothing prevents you from writing properties in the function itself.

function A(){
    this.width = 200;
}

A.height = 120;

If you want to access the properties written in the function from the function itself, you must use the 'callee' attribute of the 'arguments':

function A(){
    this.width = 200;
    alert(this.width +'x'+ arguments.callee.height);
}

A.height = 120;

A(); // should alert "200x120"

m90

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answered Feb 15, 2012 at 3:55

appcropolis

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Comments

user1106925 · Accepted Answer · 2012-02-15 01:29:17Z

1

"Is there a way to accomplish this using curly braces to create the object?"

No, there's no official syntax to create callable objects other than creating a Function object.

answered Feb 15, 2012 at 1:29

user1106925

jasonjifly · Accepted Answer · 2012-02-15 04:50:25Z

0

by the first way, A is a function, you can use it like this: A();

by the second way, A is an object

answered Feb 15, 2012 at 4:50

jasonjifly

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