/** 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