33 lines
702 B
JavaScript
33 lines
702 B
JavaScript
'use strict';
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/**
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* Throttle decorator
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* @param {Function} fn
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* @param {Number} freq
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* @return {Function}
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*/
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function throttle(fn, freq) {
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let timestamp = 0;
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const threshold = 1000 / freq;
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let timer = null;
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return function throttled(force, args) {
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const now = Date.now();
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if (force || now - timestamp > threshold) {
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if (timer) {
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clearTimeout(timer);
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timer = null;
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}
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timestamp = now;
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return fn.apply(null, args);
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}
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if (!timer) {
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timer = setTimeout(() => {
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timer = null;
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timestamp = Date.now();
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return fn.apply(null, args);
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}, threshold - (now - timestamp));
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}
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};
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}
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export default throttle;
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