import { ExtensionCodec } from '@msgpack/msgpack';
import { WeftError } from '../weft-error.ts';
declare const EXTENSION_TYPE_REGEXP = 2;
export declare class RegExpExtensionDecodeError extends WeftError<'RegExpExtensionDecodeError'> {
    readonly extensionType: typeof EXTENSION_TYPE_REGEXP;
    readonly source: string;
    readonly flags: string;
    readonly sourceByteLength: number;
    constructor(parameters: {
        source: string;
        flags: string;
        sourceByteLength: number;
        reason: string;
        cause?: unknown;
    });
}
export declare const extensionCodec: ExtensionCodec<undefined>;
/**
 * Recursively replace `undefined` with the sentinel so msgpack's encoder
 * routes it through the extension codec instead of encoding it as null.
 */
export declare function replaceUndefined(value: unknown, visited: Set<object>): unknown;
export {};