46 lines
1.1 KiB
JavaScript
46 lines
1.1 KiB
JavaScript
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function throttle(func, wait, options) {
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var timeout = void 0,
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context = void 0,
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args = void 0,
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result = void 0;
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var previous = 0;
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if (!options) options = {};
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var later = function later() {
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previous = options.leading === false ? 0 : Date.now();
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timeout = null;
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result = func.apply(context, args);
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if (!timeout) context = args = null;
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};
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var throttled = function throttled() {
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var now = Date.now();
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if (!previous && options.leading === false) previous = now;
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var remaining = wait - (now - previous);
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context = this;
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args = arguments;
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if (remaining <= 0 || remaining > wait) {
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if (timeout) {
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clearTimeout(timeout);
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timeout = null;
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}
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previous = now;
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result = func.apply(context, args);
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if (!timeout) context = args = null;
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} else if (!timeout && options.trailing !== false) {
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timeout = setTimeout(later, remaining);
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}
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return result;
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};
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throttled.cancel = function () {
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clearTimeout(timeout);
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previous = 0;
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timeout = context = args = null;
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};
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return throttled;
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}
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module.exports = throttle;
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