import type { REnvironmentInformation } from './environment';
/**
 * Adds all writes of `next` to `base` (i.e., the operations of `next` *might* happen).
 */
export declare function appendEnvironment(base: REnvironmentInformation, next: REnvironmentInformation | undefined): REnvironmentInformation;
export declare function appendEnvironment(base: REnvironmentInformation | undefined, next: REnvironmentInformation): REnvironmentInformation;
export declare function appendEnvironment(base: undefined, next: undefined): undefined;
export declare function appendEnvironment(base: REnvironmentInformation | undefined, next: REnvironmentInformation | undefined): REnvironmentInformation | undefined;