import type { OperationVariables } from '@apollo/client';
import type { Constructor } from '@apollo-elements/core/types';
import type { ApolloSubscriptionElement } from '@apollo-elements/core/types';
type MixinInstance<B extends Constructor> = B & {
    new <D, V extends OperationVariables = OperationVariables>(...a: any[]): InstanceType<B> & ApolloSubscriptionElement<D, V>;
    documentType: 'subscription';
};
declare function ApolloSubscriptionMixinImpl<B extends Constructor>(superclass: B): MixinInstance<B>;
/**
 * `ApolloSubscriptionMixin`: class mixin for apollo-subscription elements.
 */
export declare const ApolloSubscriptionMixin: typeof ApolloSubscriptionMixinImpl;
export {};