Throttle

Throttle.js

/**
 * @param {Function} fn - Função a ser executada
 * @param {Number} time - Tempo em milisegundos
 */
function throttle (fn, time) {
  var ctx
  var args
  var result
  var timeout = null
  var previous = 0

  var later = function () {
    previous = 0
    timeout = null
    result = fn.apply(ctx, args)
    ctx = null
    args = null
  }
  
  return function() {
    var now = Date.now()
    if(!previous) {
      previous = now
    }
    
    var remaining = time - (now - previous)
    var context = this
    var args = arguments
    if(remaining <= 0) {
      clearTimeout(timeout)
      timeout = null
      previous = now
      result = fn.apply(ctx, args)
      context = null
      args = null
    } else if(!timeout) {
      timeout = setTimeout(later, remaining)
    }
    return result
  }
}