skiplast.js

  var SkipLastObservable = (function (__super__) {
    inherits(SkipLastObservable, __super__);
    function SkipLastObservable(source, c) {
      this.source = source;
      this._c = c;
      __super__.call(this);
    }

    SkipLastObservable.prototype.subscribeCore = function (o) {
      return this.source.subscribe(new SkipLastObserver(o, this._c));
    };

    return SkipLastObservable;
  }(ObservableBase));

  var SkipLastObserver = (function (__super__) {
    inherits(SkipLastObserver, __super__);
    function SkipLastObserver(o, c) {
      this._o = o;
      this._c = c;
      this._q = [];
      __super__.call(this);
    }

    SkipLastObserver.prototype.next = function (x) {
      this._q.push(x);
      this._q.length > this._c && this._o.onNext(this._q.shift());
    };

    SkipLastObserver.prototype.error = function (e) {
      this._o.onError(e);
    };

    SkipLastObserver.prototype.completed = function () {
      this._o.onCompleted();
    };

    return SkipLastObserver;
  }(AbstractObserver));

  /**
   *  Bypasses a specified number of elements at the end of an observable sequence.
   * @description
   *  This operator accumulates a queue with a length enough to store the first `count` elements. As more elements are
   *  received, elements are taken from the front of the queue and produced on the result sequence. This causes elements to be delayed.
   * @param count Number of elements to bypass at the end of the source sequence.
   * @returns {Observable} An observable sequence containing the source sequence elements except for the bypassed ones at the end.
   */
  observableProto.skipLast = function (count) {
    if (count < 0) { throw new ArgumentOutOfRangeError(); }
    return new SkipLastObservable(this, count);
  };