Retrieve value from an arrow function (popmotion's pointer X position)

Question

I need to store the pointer X position in a variable. According popmotion documentation (See link here) the following would do the trick:

import { pointer } from 'popmotion';
pointer().start(({ x }) => console.log(x));

in fact, by using the code above the exact value of x is shown in the console, but I am having troubles in using the value in my code.

I have already tried:

const X = pointer().start(({ x }) => x);
const X = pointer().start(({ x }) => { return x; });

but console.log(X) returns {stop: ƒ}

I am not very familiar with arrow functions and I appreciate any help, thanks

`let X; pointer().start(({ x }) => X = x);` but bear in mind that if `start` is asynchronous, `X` will be `undefined` untill `start` finishes its work — ibrahim mahrir, Feb 16 '19 at 22:41
The `.start` callback runs asynchronously, when the cursor moves. — CertainPerformance, Feb 16 '19 at 22:42

score 0 · Accepted Answer · answered Feb 16 '19 at 22:40

0

 let x;
 pointer.start(it => x = it.x);

Note that x will be undefined until start calls back.

answered Feb 16 '19 at 22:40

Jonas Wilms

1 Answers1