Space state

The hardest thing to convey about this store in prose is that effects are returned, not performed. Below, notify-chat and typing-timer land in the right-hand pane as plain data — nothing plays a sound, nothing asks for notification permission, nothing starts a timer. What any of it means is your call.

What to try

• Press member-joined. A log line lands in chatLines and two effects come back: sound and notify-join. The log text is <log.joined> because this demo passes a t that just marks the key — the store never picks wording itself.
• Press typing, then press it again. The second one returns the same state reference, so a subscriber would not re-render. The typing-timer effect still comes back both times, because the timer has to be re-armed even when the display did not change.
• Press chat while someone is typing. You get typing-timer-clear alongside sound and notify-chat — removing the indicator and cancelling the pending 3-second timer are one atomic step.

The code behind it

import { createSpaceStore } from '@insession/space-state';

const store = createSpaceStore({
  selfName: 'you',
  t: (key) => key,              // any resolver; the identity function is fine in tests
  getPresence: () => 'active',
});

// You decide what an effect means.
store.onEffect((effect) => {
  if (effect.type === 'sound') playSound(effect.sound);
  if (effect.type === 'notify-chat') notify(`${effect.name}: ${effect.text}`);
});

// Inbound messages fold through a pure reducer.
store.receive({ type: 'chat', name: 'ren', text: 'hello' });

store.getState().chatLines.at(-1);

Because receive takes plain objects and effects are plain descriptors, a full state transition is assertable under node --test — no server, no browser, no sockets. That is the same property this page relies on to run entirely in your browser.

See the package reference for the full effect union, the store methods, and the plugin contract.