33 lines
820 B
JavaScript
33 lines
820 B
JavaScript
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module.exports = throttle;
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/**
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* Returns a new function that, when invoked, invokes `func` at most once per `wait` milliseconds.
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*
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* @param {Function} func Function to wrap.
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* @param {Number} wait Number of milliseconds that must elapse between `func` invocations.
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* @return {Function} A new function that wraps the `func` function passed in.
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*/
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function throttle (func, wait) {
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var ctx, args, rtn, timeoutID; // caching
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var last = 0;
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return function throttled () {
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ctx = this;
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args = arguments;
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var delta = new Date() - last;
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if (!timeoutID)
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if (delta >= wait) call();
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else timeoutID = setTimeout(call, wait - delta);
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return rtn;
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};
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function call () {
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timeoutID = 0;
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last = +new Date();
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rtn = func.apply(ctx, args);
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ctx = null;
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args = null;
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}
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}
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