31 lines
750 B
JavaScript
31 lines
750 B
JavaScript
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/**
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* Module exports.
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*/
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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 one time per
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* `wait` milliseconds.
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*
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* @param {Function} func The `Function` instance to wrap.
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* @param {Number} wait The minimum number of milliseconds that must elapse in between `func` invokations.
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* @return {Function} A new function that wraps the `func` function passed in.
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* @api public
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*/
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function throttle (func, wait) {
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var rtn; // return value
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var last = 0; // last invokation timestamp
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return function throttled () {
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var now = new Date().getTime();
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var delta = now - last;
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if (delta >= wait) {
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rtn = func.apply(this, arguments);
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last = now;
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}
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return rtn;
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};
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}
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