47 lines
1.8 KiB
JavaScript
47 lines
1.8 KiB
JavaScript
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import { operate } from '../util/lift';
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import { createOperatorSubscriber } from './OperatorSubscriber';
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import { innerFrom } from '../observable/innerFrom';
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export const defaultThrottleConfig = {
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leading: true,
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trailing: false,
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};
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export function throttle(durationSelector, config = defaultThrottleConfig) {
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return operate((source, subscriber) => {
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const { leading, trailing } = config;
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let hasValue = false;
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let sendValue = null;
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let throttled = null;
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let isComplete = false;
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const endThrottling = () => {
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throttled === null || throttled === void 0 ? void 0 : throttled.unsubscribe();
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throttled = null;
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if (trailing) {
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send();
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isComplete && subscriber.complete();
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}
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};
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const cleanupThrottling = () => {
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throttled = null;
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isComplete && subscriber.complete();
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};
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const startThrottle = (value) => (throttled = innerFrom(durationSelector(value)).subscribe(createOperatorSubscriber(subscriber, endThrottling, cleanupThrottling)));
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const send = () => {
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if (hasValue) {
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hasValue = false;
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const value = sendValue;
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sendValue = null;
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subscriber.next(value);
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!isComplete && startThrottle(value);
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}
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};
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source.subscribe(createOperatorSubscriber(subscriber, (value) => {
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hasValue = true;
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sendValue = value;
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!(throttled && !throttled.closed) && (leading ? send() : startThrottle(value));
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}, () => {
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isComplete = true;
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!(trailing && hasValue && throttled && !throttled.closed) && subscriber.complete();
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}));
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});
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}
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//# sourceMappingURL=throttle.js.map
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