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var debounce = require('./debounce'),    isObject = require('./isObject');
/** Error message constants. */var FUNC_ERROR_TEXT = 'Expected a function';
/** * Creates a throttled function that only invokes `func` at most once per * every `wait` milliseconds. The throttled function comes with a `cancel` * method to cancel delayed `func` invocations and a `flush` method to * immediately invoke them. Provide `options` to indicate whether `func` * should be invoked on the leading and/or trailing edge of the `wait` * timeout. The `func` is invoked with the last arguments provided to the * throttled function. Subsequent calls to the throttled function return the * result of the last `func` invocation. * * **Note:** If `leading` and `trailing` options are `true`, `func` is * invoked on the trailing edge of the timeout only if the throttled function * is invoked more than once during the `wait` timeout. * * If `wait` is `0` and `leading` is `false`, `func` invocation is deferred * until to the next tick, similar to `setTimeout` with a timeout of `0`. * * See [David Corbacho's article](https://css-tricks.com/debouncing-throttling-explained-examples/) * for details over the differences between `_.throttle` and `_.debounce`. * * @static * @memberOf _ * @since 0.1.0 * @category Function * @param {Function} func The function to throttle. * @param {number} [wait=0] The number of milliseconds to throttle invocations to. * @param {Object} [options={}] The options object. * @param {boolean} [options.leading=true] *  Specify invoking on the leading edge of the timeout. * @param {boolean} [options.trailing=true] *  Specify invoking on the trailing edge of the timeout. * @returns {Function} Returns the new throttled function. * @example * * // Avoid excessively updating the position while scrolling. * jQuery(window).on('scroll', _.throttle(updatePosition, 100)); * * // Invoke `renewToken` when the click event is fired, but not more than once every 5 minutes. * var throttled = _.throttle(renewToken, 300000, { 'trailing': false }); * jQuery(element).on('click', throttled); * * // Cancel the trailing throttled invocation. * jQuery(window).on('popstate', throttled.cancel); */function throttle(func, wait, options) {  var leading = true,      trailing = true;
  if (typeof func != 'function') {    throw new TypeError(FUNC_ERROR_TEXT);  }  if (isObject(options)) {    leading = 'leading' in options ? !!options.leading : leading;    trailing = 'trailing' in options ? !!options.trailing : trailing;  }  return debounce(func, wait, {    'leading': leading,    'maxWait': wait,    'trailing': trailing  });}
module.exports = throttle;