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node_modules/web-worker/README.md

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+<h1 align="center">
+  web-worker
+  <a href="https://www.npmjs.org/package/web-worker"><img src="https://img.shields.io/npm/v/web-worker.svg?style=flat-square" alt="npm"></a>
+</h1>
+<p align="center">
+  Native cross-platform Web Workers. Works in published npm modules.
+</p>
+<p align="center">
+  <img src="https://user-images.githubusercontent.com/105127/79602228-1998bf00-80b8-11ea-91e4-26b212aabaa2.png" width="1000" alt="">
+</p>
+
+**In Node**, it's a web-compatible Worker implementation atop Node's [worker_threads](https://nodejs.org/api/worker_threads.html).
+
+**In the browser** (and when bundled for the browser), it's simply an alias of `Worker`.
+
+### Features
+
+_Here's how this is different from worker_threads:_
+
+- makes Worker code compatible across browser and Node
+- supports Module Workers (`{type:'module'}`) natively in Node 12.8+
+- uses DOM-style events (`Event.data`, `Event.type`, etc)
+- supports event handler properties (`worker.onmessage=..`)
+- `Worker()` accepts a module URL, Blob URL or Data URL
+- emulates browser-style [WorkerGlobalScope] within the worker
+
+### Usage Example
+
+In its simplest form:
+
+```js
+import Worker from 'web-worker';
+
+const worker = new Worker('data:,postMessage("hello")');
+worker.onmessage = e => console.log(e.data);  // "hello"
+```
+
+<table>
+<thead><tr><th><strong>main.js</strong></th><th><strong>worker.js</strong></th></tr></thead>
+<tbody><tr><td>
+
+```js
+import Worker from 'web-worker';
+
+const url = new URL('./worker.js', import.meta.url);
+const worker = new Worker(url);
+
+worker.addEventListener('message', e => {
+  console.log(e.data)  // "hiya!"
+});
+
+worker.postMessage('hello');
+```
+
+</td><td valign="top">
+
+```js
+addEventListener('message', e => {
+  if (e.data === 'hello') {
+    postMessage('hiya!');
+  }
+});
+```
+
+</td></tr></tbody>
+</table>
+
+👉 Notice how `new URL('./worker.js', import.meta.url)` is used above to load the worker relative to the current module instead of the application base URL. Without this, Worker URLs are relative to a document's URL, which in Node.js is interpreted to be `process.cwd()`.
+
+> _Support for this pattern in build tools and test frameworks is still limited. We are [working on growing this](https://github.com/developit/web-worker/issues/4)._
+
+### Module Workers
+
+Module Workers are supported in Node 12.8+ using this plugin, leveraging Node's native ES Modules support.
+In the browser, they can be used natively in Chrome 80+, or in all browsers via [worker-plugin] or [rollup-plugin-off-main-thread]. As with classic workers, there is no difference in usage between Node and the browser:
+
+<table>
+<thead><tr><th><strong>main.mjs</strong></th><th><strong>worker.mjs</strong></th></tr></thead>
+<tbody><tr><td>
+
+```js
+import Worker from 'web-worker';
+
+const worker = new Worker(
+  new URL('./worker.mjs', import.meta.url),
+  { type: 'module' }
+);
+worker.addEventListener('message', e => {
+  console.log(e.data)  // "200 OK"
+});
+worker.postMessage('https://httpstat.us/200');
+```
+
+</td><td valign="top">
+
+```js
+import fetch from 'isomorphic-fetch';
+
+addEventListener('message', async e => {
+  const url = e.data;
+  const res = await fetch(url)
+  const text = await res.text();
+  postMessage(text);
+});
+```
+
+</td></tr></tbody>
+</table>
+
+
+### Data URLs
+
+Instantiating Worker using a Data URL is supported in both module and classic workers:
+
+```js
+import Worker from 'web-worker';
+
+const worker = new Worker(`data:application/javascript,postMessage(42)`);
+worker.addEventListener('message', e => {
+  console.log(e.data)  // 42
+});
+```
+
+### Special Thanks
+
+This module aims to provide a simple and forgettable piece of infrastructure,
+and as such it needed an obvious and descriptive name.
+[@calvinmetcalf](https://github.com/calvinmetcalf), who you may recognize as the author of [Lie](https://github.com/calvinmetcalf/lie) and other fine modules, gratiously offered up the name from his `web-worker` package.
+Thanks Calvin!
+
+
+[worker-plugin]: https://github.com/googlechromelabs/worker-plugin
+[rollup-plugin-off-main-thread]: https://github.com/surma/rollup-plugin-off-main-thread
+[WorkerGlobalScope]: https://developer.mozilla.org/en-US/docs/Web/API/WorkerGlobalScope