forked from Backwards/backwards.dev
66 lines
1.5 KiB
JavaScript
66 lines
1.5 KiB
JavaScript
import { T as noop, a4 as subscribe_to_store } from "./index.js";
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import { a as safe_not_equal } from "./equality.js";
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const subscriber_queue = [];
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function readable(value, start) {
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return {
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subscribe: writable(value, start).subscribe
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};
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}
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function writable(value, start = noop) {
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let stop = null;
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const subscribers = /* @__PURE__ */ new Set();
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function set(new_value) {
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if (safe_not_equal(value, new_value)) {
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value = new_value;
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if (stop) {
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const run_queue = !subscriber_queue.length;
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for (const subscriber of subscribers) {
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subscriber[1]();
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subscriber_queue.push(subscriber, value);
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}
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if (run_queue) {
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for (let i = 0; i < subscriber_queue.length; i += 2) {
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subscriber_queue[i][0](subscriber_queue[i + 1]);
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}
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subscriber_queue.length = 0;
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}
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}
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}
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}
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function update(fn) {
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set(fn(
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/** @type {T} */
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value
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));
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}
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function subscribe(run, invalidate = noop) {
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const subscriber = [run, invalidate];
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subscribers.add(subscriber);
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if (subscribers.size === 1) {
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stop = start(set, update) || noop;
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}
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run(
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/** @type {T} */
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value
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);
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return () => {
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subscribers.delete(subscriber);
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if (subscribers.size === 0 && stop) {
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stop();
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stop = null;
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}
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};
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}
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return { set, update, subscribe };
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}
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function get(store) {
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let value;
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subscribe_to_store(store, (_) => value = _)();
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return value;
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}
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export {
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get as g,
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readable as r,
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writable as w
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};
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