tiny-map

Map over promises with concurrency control. Same API as p-map, but ships both ESM and CJS with zero dependencies.

import { pMap } from "tiny-pmap";

const pages = await pMap(urls, (url) => fetch(url).then((r) => r.text()), {
  concurrency: 5,
});

~1.2 KB gzipped. Zero dependencies. Replaces p-map without the ESM-only headache.

Demo built with remotion-readme-kit

Install

npm install tiny-pmap

Usage

import { pMap } from "tiny-pmap";

const users = await pMap([1, 2, 3, 4, 5], (id) => fetchUser(id), {
  concurrency: 3,
});

Skip items from results

import { pMap, pMapSkip } from "tiny-pmap";

const adults = await pMap(users, (user) => {
  if (user.age < 18) return new pMapSkip();
  return user;
});

Async iterables

async function* generateIds() {
  for (let i = 0; i < 100; i++) yield i;
}

const results = await pMap(generateIds(), (id) => process(id), {
  concurrency: 10,
});

Collect all errors

try {
  await pMap(items, riskyOperation, { stopOnError: false, concurrency: 5 });
} catch (error) {
  // AggregateError with all failures
  console.log(error.errors);
}

Cancel with AbortSignal

const controller = new AbortController();
setTimeout(() => controller.abort(), 5000);

await pMap(urls, fetchPage, {
  concurrency: 3,
  signal: controller.signal,
});

Differences from p-map

p-map v7+ is ESM-only. If you require("p-map") in a CommonJS project, you get ERR_REQUIRE_ESM. tiny-map works with both import and require().

| | p-map | tiny-map | | ------------ | ---------------------- | ---------- | | CJS support | v5 only (v6+ ESM-only) | ESM + CJS | | Dependencies | none | 0 | | TypeScript | separate @types | native | | Export | default | named |

Migrating from p-map

- import pMap from "p-map";
+ import { pMap } from "tiny-pmap";

One line. Everything else stays the same.

API

pMap(input, mapper, options?)

Maps over input with the mapper function, limiting concurrency.

• input - Iterable or AsyncIterable
• mapper(element, index) - function returning a value or promise
• options.concurrency - max parallel executions (default: Infinity)
• options.stopOnError - throw on first error or collect all (default: true)
• options.signal - AbortSignal for cancellation

Returns Promise<NewElement[]> with results in input order.

pMapSkip

Return new pMapSkip() from the mapper to exclude that element from results.

The tiny-* family

Drop-in replacements for sindresorhus async utilities. All ship ESM + CJS with zero dependencies.

| Package | Replaces | What it does | | ------------------------------------------------------ | -------------------- | ------------------------------ | | tiny-limit | p-limit | Concurrency limiter | | tiny-map | p-map | Concurrent map with order | | tiny-retry | p-retry | Retry with exponential backoff | | tiny-queue | p-queue | Priority task queue | | tiny-ms | ms | Parse/format durations | | tiny-escape | escape-string-regexp | Escape regex chars |

Want all async utilities in one import? Use tiny-pasync.

Author

If this saved you from ERR_REQUIRE_ESM, star the repo or open an issue if something breaks.

License

MIT © Ofer Shapira