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Discussion on: Which functions/methods do you...

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Replies for: Function for prevent using try catch in all async await calls type Result<DataType> = [ Error | undefined, DataType | undefined ]...

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kevinleebuchan profile image
KevinLeeBuchan •

You should do a post on this. I use JavaScript all the time but I'm seeing syntax I'm not familiar with. I feel like I'm peeking through a window from a room I didn't know I was stuck in.

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joelbonetr profile image
JoelBonetR 🥇 • • Edited

😂 Both @c_basso and @fedyk solutions are coded in TS that can be the cause of your confusion @kevinleebuchan, here's a JS translation (guys correct me if I miss something)

/**
 * Handles promise resolution
 * @param {Promise} promise
 * @returns {any}
 */
export const go = (promise) =>
  Promise.resolve(promise)
    .then((result) => [result, null])
    .catch((error) => [null, error]);
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Usage example:

/** Retrieves Ditto data */
const getDitto = async () => {
  const [result, error] = await go(fetch('https://pokeapi.co/api/v2/pokemon/ditto'));

  if (error) console.error(error);
  else console.log(await result.json());
};

await getDitto();
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Note that the return value of the go function is always an array with two positions, the first one intended to be a successful result, the second one reserved for the error so in case it succeeds it sends [result, null] and in case it fails it sends back [null, error], this may help to understanding:

const [result, error] = ['Success!', null];

result; // 'Success!'
error; // null
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Hope it helps! 😁