24 lines
475 B
JavaScript
24 lines
475 B
JavaScript
export function observable(store) {
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const subscribers = new Set();
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const accessor = function _observable(newVal) {
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if (newVal !== undefined && store !== newVal) {
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store = newVal;
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subscribers.forEach(s => s(store));
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}
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return store;
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};
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accessor.subscribe = accessor._d = fn => {
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subscribers.add(fn);
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return () => {
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subscribers.delete(fn);
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return subscribers.size;
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};
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};
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accessor.unsubscribeAll = () => subscribers.clear();
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return accessor;
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}
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