<pacem-webworker-proxy> runs a script on a background thread and talks to it: heavy number crunching, parsing, image work, without freezing the page. Point src at the worker, send it a message, read its result.

<pacem-webworker-proxy id="primes" src="/dist/js/workers/primes.js" message="{{ #limit.value }}"></pacem-webworker-proxy>
<pacem-text text="{{ #primes.result.count }}"></pacem-text>

Usage

Start it. src is the worker's script URL (same origin); the worker starts as soon as the element is up, and a new src replaces it.

Talk to it. With autosend (the default), every change of message gets posted; turn it off and call send(…) when you mean it. What the worker posts back lands in result and fires receive.

<pacem-webworker-proxy src="/workers/resize.js" autosend="false"
                       on-receive="#preview.model = $event.detail"></pacem-webworker-proxy>

A worker has no DOM and no Pacem: it gets data, computes, posts data back. Messages are structured-cloned both ways: send plain values, objects, arrays, typed arrays.

Stop it. Changing src (or removing the element) terminates the worker on the spot, job in flight included: that's how you cancel a computation that's taking too long.

Examples

Answer as you type

autosend: every new limit goes to the worker, and the answer comes back without blocking the field.

Cancel a long job

Ask for the primes up to 100 million (about a second), then cancel quickly: emptying src terminates the worker, and setting it back starts a fresh one.