/** Result type for pure narrowing/decoding functions. */
export type NarrowResult<T> = {
    ok: true;
    value: T;
} | {
    ok: false;
    error: string;
};
/** Unwrap a NarrowResult, throwing on failure. Use at persistence boundaries. */
export declare function unwrapNarrow<T>(result: NarrowResult<T>): T;
