import { ILogger, Campaign, TrackingMethod } from '@amplitude/analytics-core';
import { ExcludeInternalReferrersOptions } from '../types';
export interface Options {
    excludeReferrers?: (string | RegExp)[];
    excludeInternalReferrers?: true | false | ExcludeInternalReferrersOptions;
    initialEmptyValue?: string;
    resetSessionOnNewCampaign?: boolean;
    trackingMethod?: TrackingMethod | TrackingMethod[];
    fallbackAttributionEvent?: boolean;
    optOut?: boolean;
}
export declare const isNewCampaign: (current: Campaign, previous: Campaign | undefined, options: Options, logger: ILogger, isNewSession?: boolean, topLevelDomain?: string) => boolean;
export declare const isExcludedReferrer: (excludeReferrers?: (string | RegExp)[], referringDomain?: string) => boolean;
export declare const isSubdomainOf: (subDomain: string, domain: string) => boolean;
export declare const createCampaignEvent: (campaign: Campaign, options: Options) => import("@amplitude/analytics-core").IdentifyEvent;
export declare const getDefaultExcludedReferrers: (cookieDomain: string | undefined) => RegExp[];
export declare const KNOWN_2LDS: string[];
export declare const getDomain: (hostnameParam?: string) => string;
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