tinylet
redlet()
and greenlet()
threading helpers for Node.js, Deno, and the
browser
async
function synchronously with redlet()
Worker
with greenlet()
redlet()
requires enabling SharedArrayBuffer
in the browser
Installation
You can install this package using npm, Yarn, or pnpm:
npm install tinylet
If you're using Deno, you can import this package from an npm CDN like
ESM>CDN or jsDelivr. You can also use Deno's new npm:
specifier to
import this package directly from npm!
import {} from "https://esm.run/tinylet";
import {} from "npm:tinylet";
If you're in the browser using a <script type="module">
tag, you can import
this package straight from an npm CDN like ESM>CDN or jsDelivr!
<script type="module">
import {} from "https://esm.run/tinylet";
</script>
Usage
You can use greenlet()
to run a function asynchronously in a web worker!
This is great for offloading complicated synchronous work (like image
processing) to a web worker so that it doesn't block the main thread.
import { greenlet } from "tinylet";
// Runs asynchronously in a worker thread.
const f = greenlet((a, b) => {
let n = 0;
for (let i = 0; i < 1000000000; i++) {
if (i % 5 === 0) n += a;
if (i % 10 === 0) n -= i;
if (i % 60 === 0) n *= 2;
if (i % 75 === 0) n /= b;
}
return n;
});
// Takes ~3 seconds to run, but doesn't block the main thread!
console.log(await f(1, 200));
//=> -2066010092.990183
If you want to go the other way and run an async
function in a worker thread,
but still get the result back synchronously in the current thread, you can use
redlet()
! This is useful when you absolutely need something to be
synchronous (like for WASM interop) but the underlying web API is asynchronous.
import { redlet } from "tinylet";
// Runs in a worker thread and uses Atomics.wait() to block the current thread.
const f = redlet(async (u) => {
const response = await fetch(u);
return await response.json();
});
// Takes 1 second to run and BLOCKS the current thread!
console.log(f("https://jsonplaceholder.typicode.com/todos/1"));
//=> { "userId": 1, "id": 1, "title": "delectus aut autem", "completed": false }
redlet()
works in browsers, only if you've enabled SharedArrayBuffer
.
Even then, you can't call redlet()
on the main thread; it only works in worker
threads. This is because browsers don't allow Atomics.wait()
to be called on
the main thread.
redlet()
will always work in Node.js and other server-side environments
like Deno. Those contexts all enable SharedArrayBuffer
by default, and support
Atomics.wait()
on the main thread!
Development
TODO: Add development blurb