text: var __extends = (this && this.__extends) || function (d, b) {
      for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p];
      function __() { this.constructor = d; }
      d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
  };
  define(["require", "exports", '../Subscriber'], function (require, exports, Subscriber_1) {
      "use strict";
      /**
       * Counts the number of emissions on the source and emits that number when the
       * source completes.
       *
       * <span class="informal">Tells how many values were emitted, when the source
       * completes.</span>
       *
       * <img src="./img/count.png" width="100%">
       *
       * `count` transforms an Observable that emits values into an Observable that
       * emits a single value that represents the number of values emitted by the
       * source Observable. If the source Observable terminates with an error, `count`
       * will pass this error notification along without emitting an value first. If
       * the source Observable does not terminate at all, `count` will neither emit
       * a value nor terminate. This operator takes an optional `predicate` function
       * as argument, in which case the output emission will represent the number of
       * source values that matched `true` with the `predicate`.
       *
       * @example <caption>Counts how many seconds have passed before the first click happened</caption>
       * var seconds = Rx.Observable.interval(1000);
       * var clicks = Rx.Observable.fromEvent(document, 'click');
       * var secondsBeforeClick = seconds.takeUntil(clicks);
       * var result = secondsBeforeClick.count();
       * result.subscribe(x => console.log(x));
       *
       * @example <caption>Counts how many odd numbers are there between 1 and 7</caption>
       * var numbers = Rx.Observable.range(1, 7);
       * var result = numbers.count(i => i % 2 === 1);
       * result.subscribe(x => console.log(x));
       *
       * @see {@link max}
       * @see {@link min}
       * @see {@link reduce}
       *
       * @param {function(value: T, i: number, source: Observable<T>): boolean} [predicate] A
       * boolean function to select what values are to be counted. It is provided with
       * arguments of:
       * - `value`: the value from the source Observable.
       * - `index`: the (zero-based) "index" of the value from the source Observable.
       * - `source`: the source Observable instance itself.
       * @return {Observable} An Observable of one number that represents the count as
       * described above.
       * @method count
       * @owner Observable
       */
      function count(predicate) {
          return this.lift(new CountOperator(predicate, this));
      }
      exports.count = count;
      var CountOperator = (function () {
          function CountOperator(predicate, source) {
              this.predicate = predicate;
              this.source = source;
          }
          CountOperator.prototype.call = function (subscriber, source) {
              return source._subscribe(new CountSubscriber(subscriber, this.predicate, this.source));
          };
          return CountOperator;
      }());
      /**
       * We need this JSDoc comment for affecting ESDoc.
       * @ignore
       * @extends {Ignored}
       */
      var CountSubscriber = (function (_super) {
          __extends(CountSubscriber, _super);
          function CountSubscriber(destination, predicate, source) {
              _super.call(this, destination);
              this.predicate = predicate;
              this.source = source;
              this.count = 0;
              this.index = 0;
          }
          CountSubscriber.prototype._next = function (value) {
              if (this.predicate) {
                  this._tryPredicate(value);
              }
              else {
                  this.count++;
              }
          };
          CountSubscriber.prototype._tryPredicate = function (value) {
              var result;
              try {
                  result = this.predicate(value, this.index++, this.source);
              }
              catch (err) {
                  this.destination.error(err);
                  return;
              }
              if (result) {
                  this.count++;
              }
          };
          CountSubscriber.prototype._complete = function () {
              this.destination.next(this.count);
              this.destination.complete();
          };
          return CountSubscriber;
      }(Subscriber_1.Subscriber));
  });
  //# sourceMappingURL=count.js.map