Javascript is not returning objects as expected

confusedJS 0
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Javascript (or Node.js) is not returning objects as expected.

The following code logs an empty array.

const _sodium = require('libsodium-wrappers');

const sodium = (async () => {
  await _sodium.ready;
  return _sodium;
})();

console.log(Object.getOwnPropertyNames(sodium));

On the other hand, the following code works as expected.

const _sodium = require('libsodium-wrappers');

(async () => {
  await _sodium.ready;
  const sodium = _sodium;
  console.log(Object.getOwnPropertyNames(sodium));
})();

In the first code snippet, it seems like the sodium object is tied to its lexical environment, which would explain why an empty array is printed. I would be interested in what's going on here (including an explanation of what's going on under the hood). Thanks.

libsodium node.js javascript
1 Answers

It's not about lexical context.

You just not awaiting for ready in the first example.

First example simplified:

(async() => {
  console.log('start')
  await new Promise(r => setTimeout(r, 3000))
  console.log('finish')
})()

Second example simplified:

console.log('start');
(async() => {
  await new Promise(r => setTimeout(r, 3000))
})();
console.log('finish')

Konrad Linkowski0
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