import * as t from './types';
export declare function stringify(data: any, errorMessage: () => string): string;
export declare function parseJson(args: {
    url: string;
    text: string;
}): t.Json;
export declare function toRawHeaders(input?: t.IHttpHeaders): Headers;
export declare function fromRawHeaders(input: Headers): t.IHttpHeaders;
export declare function headerValue(key: string, headers?: t.IHttpHeaders): string;
export declare function isFormData(headers?: t.IHttpHeaders): boolean;
export declare function isStream(value?: ReadableStream<Uint8Array>): boolean;
export declare const response: {
    fromPayload(payload: t.IHttpRespondPayload, modifications?: {
        data?: any;
        headers?: t.IHttpHeaders | undefined;
    }): Promise<t.IHttpResponse>;
    fromFetch(res: t.IHttpFetchResponse): Promise<t.IHttpResponse>;
    toContentType(headers: t.IHttpHeaders): t.IHttpContentType;
};