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