import type { IncomingMessage, OutgoingMessage } from '../types/iframe-events';
export declare function resolveParentOrigin(): string;
export declare function submitPostMessage<T extends OutgoingMessage>(message: T, targetOrigin?: string): void;
export declare function isOutgoingMessage<T extends OutgoingMessage['type']>(msg: OutgoingMessage, type: T): msg is Extract<OutgoingMessage, {
    type: T;
}>;
export declare function isIncomingMessage<T extends IncomingMessage['type']>(msg: IncomingMessage, type: T): msg is Extract<IncomingMessage, {
    type: T;
}>;