text: import Subscriber from '../Subscriber';
  import tryCatch from '../util/tryCatch';
  import { errorObject } from '../util/errorObject';
  import bindCallback from '../util/bindCallback';
  export default function distinctUntilChanged(compare, thisArg) {
      return this.lift(new DistinctUntilChangedOperator(thisArg ?
          bindCallback(compare, thisArg, 2) :
          compare));
  }
  class DistinctUntilChangedOperator {
      constructor(compare) {
          this.compare = compare;
      }
      call(subscriber) {
          return new DistinctUntilChangedSubscriber(subscriber, this.compare);
      }
  }
  class DistinctUntilChangedSubscriber extends Subscriber {
      constructor(destination, compare) {
          super(destination);
          this.hasValue = false;
          if (typeof compare === 'function') {
              this.compare = compare;
          }
      }
      compare(x, y) {
          return x === y;
      }
      _next(x) {
          let result = false;
          if (this.hasValue) {
              result = tryCatch(this.compare)(this.value, x);
              if (result === errorObject) {
                  this.destination.error(errorObject.e);
                  return;
              }
          }
          else {
              this.hasValue = true;
          }
          if (Boolean(result) === false) {
              this.value = x;
              this.destination.next(x);
          }
      }
  }
  