Why is my function not working?

Question

Now that I have my other questions answered, this function isn't working. What's wrong?

Weird JavaScript statement, what does it mean?

How to handle click event in javascript?

function myFunc() {
    return
    {
        obj = this;
    };
}

I'm tempted to flag this question to be closed, but several people have already answered it. You have two syntax errors in that function . Fix both of those, and it'll work as expected. — Mark Bessey, Mar 28 '11 at 18:48

score 6 · Answer 1 · answered Mar 28 '11 at 18:41

The syntax to create an object literal is:

{ foo: bar }

not

{ foo = bar }

Additionally, in JavaScript a new line can terminate a statement. By placing a new line after the return you are returning undefined and the object literal code is never reached. JSLint can pick up on this type of problem.

score 6 · Accepted Answer · answered Mar 28 '11 at 18:43

6

Your function is not working due to how JavaScript auto-adds semicolons.

Your return statement is being read by JavaScript as:

return;
{
    obj: this;
};

You need to put the { on the same line as return:

return{
    obj: this;
};

Also, objects need to be {name: value}.

answered Mar 28 '11 at 18:43

gen_Eric

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I tried but its still not working. I don't think your stuff is right. – Stack Guru Mar 28 '11 at 18:43
You are right about the semicolons, but `obj = this` isn't allowed inside an object constructor. Only in a block. I think the `=` needs to become a colon. – Mike Samuel Mar 28 '11 at 18:44
@Mike: Yeah, I fixed that... I need more coffee. – gen_Eric Mar 28 '11 at 18:45

score 5 · Answer 3 · answered Mar 28 '11 at 18:42

5

It's because of semicolon injection.

This:

return
  { myProperty: "hello world" };

Is parsed like this:

<< return statement >>
<< pointless object literal expression >>

And not as:

<< return statement with return value expression >>

To return an object value, your code has to look like this:

return {
  myProperty: "hello world"
};

with the { on the same line as return.

answered Mar 28 '11 at 18:42

Pointy

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But I have a firewall to prevent that, now what? – Stack Guru Mar 28 '11 at 18:42
2

I think you mean semicolon insertion. – Mike Samuel Mar 28 '11 at 18:43
5

@Stack Guru, where can I get that firewall? – gen_Eric Mar 28 '11 at 18:43
@Mike Samuel -- Thanks!! I was trying to type fast :-) – Pointy Mar 28 '11 at 18:44
Too bad you fixed your mistake too soon to be tracked by SO's revision history, now I don't know what the fuss was about. ;-) – Marcel Korpel Mar 28 '11 at 19:05
1

@Marcel Korpel I had originally typed "newline injection" :-) – Pointy Mar 28 '11 at 19:15

Why is my function not working?

3 Answers3