import { Inspector } from './inspector'; export declare abstract class Assertion { abstract readonly description: string; abstract assertUsing(inspector: InspectorClass): boolean; /** * Assert this thing and another thing */ and(assertion: Assertion): Assertion; assertOrThrow(inspector: InspectorClass): void; } export declare abstract class JestFriendlyAssertion extends Assertion { /** * Generates an error message that can be used by Jest. */ abstract generateErrorMessage(): string; } export declare function not(assertion: Assertion): Assertion;