will export function() be called multiple times in javascript?

Question

I wonder if this

const getData = () => {
  const data = 1; // simplified complicated operations 
  return data;
};

export default getData();

is any performance difference than this:

const getData = () => {
  const data = 1;
  return data;
};

const toexport = getData(); // cache to a variable before exporting
export default toexport;

The question boils down to how export actually works. I read many articles and I can manage to make it work, but I haven't understood what it does under the hood (couldn't find an article about my question).

What if an export is imported from difference import, will the getData() be called once or being called for each import?

function getData() {
  console.log('getData');
  return 1;
}

// will `export default getData();` be like this
const importSomeWhere = getData();
const importSomeWhereElse = getData();



// or this?
const exportCached = getData();

const importSomeWhere2 = exportCached;
const importSomeWhereElse2 = exportCached;

Answer 1

It will be evaluated only once. Here's example from What Happens When a Module Is Imported Twice?

In increment.js, we declare a variable called counter

let counter = 0;
counter++;

export default counter;

In consumer.js we import 2 times, but the counter is evaluated once for the first import

import counter1 from './increment';
import counter2 from './increment';

counter1; // => 1
counter2; // => 1