text: /** PURE_IMPORTS_START tslib,_Subscriber PURE_IMPORTS_END */
  import * as tslib_1 from "tslib";
  import { Subscriber } from '../Subscriber';
  export function distinctUntilChanged(compare, keySelector) {
      return function (source) { return source.lift(new DistinctUntilChangedOperator(compare, keySelector)); };
  }
  var DistinctUntilChangedOperator = /*@__PURE__*/ (function () {
      function DistinctUntilChangedOperator(compare, keySelector) {
          this.compare = compare;
          this.keySelector = keySelector;
      }
      DistinctUntilChangedOperator.prototype.call = function (subscriber, source) {
          return source.subscribe(new DistinctUntilChangedSubscriber(subscriber, this.compare, this.keySelector));
      };
      return DistinctUntilChangedOperator;
  }());
  var DistinctUntilChangedSubscriber = /*@__PURE__*/ (function (_super) {
      tslib_1.__extends(DistinctUntilChangedSubscriber, _super);
      function DistinctUntilChangedSubscriber(destination, compare, keySelector) {
          var _this = _super.call(this, destination) || this;
          _this.keySelector = keySelector;
          _this.hasKey = false;
          if (typeof compare === 'function') {
              _this.compare = compare;
          }
          return _this;
      }
      DistinctUntilChangedSubscriber.prototype.compare = function (x, y) {
          return x === y;
      };
      DistinctUntilChangedSubscriber.prototype._next = function (value) {
          var key;
          try {
              var keySelector = this.keySelector;
              key = keySelector ? keySelector(value) : value;
          }
          catch (err) {
              return this.destination.error(err);
          }
          var result = false;
          if (this.hasKey) {
              try {
                  var compare = this.compare;
                  result = compare(this.key, key);
              }
              catch (err) {
                  return this.destination.error(err);
              }
          }
          else {
              this.hasKey = true;
          }
          if (!result) {
              this.key = key;
              this.destination.next(value);
          }
      };
      return DistinctUntilChangedSubscriber;
  }(Subscriber));
  //# sourceMappingURL=distinctUntilChanged.js.map
  