import type { CompactUndefinedOp } from '../codec/compact/types';
import { AbstractPredicateOp } from './AbstractPredicateOp';
import type { OperationUndefined } from '../types';
import { OPCODE } from '../constants';
import type { AbstractOp } from './AbstractOp';
/**
 * @category JSON Predicate
 */
export declare class OpUndefined extends AbstractPredicateOp<'undefined'> {
    op(): "undefined";
    code(): OPCODE;
    test(doc: unknown): boolean;
    toJson(parent?: AbstractOp): OperationUndefined;
    toCompact(parent: undefined | AbstractOp, verbose: boolean): CompactUndefinedOp;
}
