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How does the resolve function work here? It is passed an object where one property is an object and the other a promise. The next then suddenly receives the res

• deleted 7y ago
  [deleted]
• hoorayimhelping 7y ago
  The argument passed to `resolve` gets returned from the resolve function and becomes available to any handler that handles it with `then`. In the above example, the object is being destructured as part of the arguments. The destructuring is probably what's tripping you up. // straightforward, no magic const simpleFunction = function() { return Promise.resolve({ name: 'simpleObject' }); } simpleFunction().then(function(response) { console.log(response); // { name: 'simpleObject' } }); // alternatively, destructuring the arguments simpleFunction().then(function({ name }) { console.log(name); // 'simpleObject' });
  • deleted 7y ago
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  • korla 7y ago
    No that is not what is tripping me up, or happening. The other answer explained it, some library code was executed aeaiting the location-promise.
• thedufer 7y ago
  It iterates over all key/value pairs. For each value, if it is a promise it waits for it and replaces it with the result, while non-promises are left as-is. This is a fairly common function to have in promise libraries.
  • korla 7y ago
    That was my point. It’s not obvious to the reader that this is better since it’s a non-standard way of resolving promises. But it looks neat. I’ve never seen it, what library do you have experience with that does it this way?
    • thedufer 7y ago
      I've been out of the JavaScript world for years now, but I last used Bluebird which has Promise.props[1] with this behavior. [1] http://bluebirdjs.com/docs/api/promise.props.html http://bluebirdjs.com/docs/api/promise.props.html