39 lines
1.1 KiB
JavaScript
39 lines
1.1 KiB
JavaScript
"use strict";
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function noop() { }
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function once(emitter, name) {
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const o = once.spread(emitter, name);
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const r = o.then((args) => args[0]);
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r.cancel = o.cancel;
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return r;
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}
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(function (once) {
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function spread(emitter, name) {
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let c = null;
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const p = new Promise((resolve, reject) => {
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function cancel() {
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emitter.removeListener(name, onEvent);
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emitter.removeListener('error', onError);
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p.cancel = noop;
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}
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function onEvent(...args) {
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cancel();
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resolve(args);
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}
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function onError(err) {
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cancel();
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reject(err);
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}
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c = cancel;
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emitter.on(name, onEvent);
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emitter.on('error', onError);
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});
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if (!c) {
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throw new TypeError('Could not get `cancel()` function');
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}
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p.cancel = c;
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return p;
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}
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once.spread = spread;
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})(once || (once = {}));
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module.exports = once;
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//# sourceMappingURL=index.js.map
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