Promise.all(), Promise.race(), and Promise.any()

What pattern does this code implement?

const promises = urls.map(url => fetch(url));
Promise.allSettled(promises).then(results => {
  const failed = results
    .filter(r => r.status === 'rejected')
    .map(r => r.reason);
  const succeeded = results
    .filter(r => r.status === 'fulfilled')
    .map(r => r.value);
});

Basic error handling
Result categorization
This implements result categorization pattern: 1) Separates successes from failures, 2) Maintains all results without throwing, 3) Enables different handling for each category, 4) Preserves error information, 5) Useful for reporting and analytics, 6) Common in robust error handling systems.
Promise chaining
Request batching

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