filter function

filter.js

var isArrayLike = function (arg) {
  return arg && typeof arg.length === 'number' && arg.length > -1 && arg.length % 1 === 0 && typeof arg !== 'function'
}

var filter = (function () {
  if (Array.prototype.filter) {
    return function (arrayLikeList, filter, thisArg) {
      return Array.prototype.filter.call(arrayLikeList, filter, thisArg)
    }
  } else { // Array.prototype.filter fallback
    return function (arrayLikeList, filter, thisArg) {
      if (!isArrayLike(arrayLikeList)) throw new TypeError('Parameter arrayLikeList isn\'t array like')
      if (typeof filter !== 'function') throw new TypeError('Parameter filter is not a function')
      if (thisArg === void 0) thisArg = this
      var o = Object(arrayLikeList)
      var len = o.length >>> 0
      var res = []
      var k = 0
      while (k < len) {
        if (k in o && filter.call(thisArg, o[k], k, o)) res.push(o[k])
        k++
      }
      return res
    }
  }
})()