/** The value at `path` in a JSON tree, or undefined when any segment is
 *  missing. Array indices are their decimal strings, as the readers
 *  write them. */
export declare function getAt(json: unknown, path: string[]): unknown;
/** Write `value` at `path` in `json`, in place, creating no containers:
 *  the parent must exist, since every path an edit writes was read from
 *  the same tree first. Returns false when it does not. */
export declare function setAt(json: unknown, path: string[], value: unknown): boolean;