/**
 * Copyright 2019, OpenCensus Authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
import { SpanContext } from '../model/types';
import { HeaderGetter, HeaderSetter, Propagation } from './types';
/** No-op implementation of Propagation */
declare class NoopPropagation implements Propagation {
    extract(getter: HeaderGetter): SpanContext | null;
    inject(setter: HeaderSetter, spanContext: SpanContext): void;
    generate(): SpanContext;
}
export declare const noopPropagation: NoopPropagation;
export {};