JavaScript in 30 words
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JavaScript Promises Explained Simply

A promise is an object that may produce a value sometime in the future. Either a resolved value or a reason that it’s not resolved (e.g., a network error occurred).

const price = Promise.resolve(20);
price
  .then((amount) => amount * 2)
  .then((total) => {
    console.log(total);
    throw new Error("Payment declined");
  })
  .catch((error) => {
    console.log(error.message);
  });

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