Question

I want to include a property on an object only in the event that a variable is defined. I don’t want the property at all otherwise. I don’t even want it to equal a blank string. I’m thinking something like this:

someFunc({
    bing: "bing",
    bang: (myVar) ? myVar : undefined,
    boom: "boom"
    }, "yay");

In the event that myVar is undefined, I want this to result in the same thing as the below:

someFunc({
    bing: "bing",
    boom: "boom"
    }, "yay");

Am I doing it right?

Answer 1

There is a difference between this:

var ex1 = {foo: undefined};

and this:

var ex2 = {};

Therefore, here’s how I would do it:

var args = {
    bing: 'bing',
    boom: 'boom'
};

if (typeof myVar !== 'undefined') {
    args.bang = myVar;
}

someFunc(args, 'yay');