Javascript Variable checking shorthand

Question

I'm wondering if there's a shorthand way to write something like this in JavaScript

if (thingExists) {
    thingExists.manipulate
}

I think I remember seeing something along the lines of

thingExists?.manipulate

but that may have been TypeScript or something.

Anyway, any knowledge on that matter is appreciated,

Thanks!

Can you give a more complete example? How do you want to use such a construct? Is `thingExists.manipulate` supposed to be a value of a property or a function call? — Code-Apprentice, Aug 22 '18 at 00:04
You can short circuit it with `&&`. `thingExists && thingExists.manipulate`, although it's not that readable. — Wreigh, Aug 22 '18 at 00:06
Yes, JS doesn’t have `?.` yet. There are [proposals](https://stackoverflow.com/a/48286392/4642212) for this. — Sebastian Simon, Aug 22 '18 at 00:17

ibrahim mahrir · Answer 1 · 2018-08-22T00:20:53.703

0

You can use && for short circuiting:

    thingExists && thingExists.manipulate

thingExists.manipulate will be evaluated if and only if thingExists is truthy.

Example:

var obj = { func: function() { console.log("func is called"); } };

obj && obj.func();                        // => func is called 

var falsy = null;

falsy && falsy.imaginaryFunc();           // => nothing

edited Aug 22 '18 at 00:20

answered Aug 22 '18 at 00:15

ibrahim mahrir

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Javascript Variable checking shorthand

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