export declare const ERR_MSG_TRANSFORMER_MUST_NOT_RETURN_NO_VAL_FOR_MAYBE: string;
export declare const ERR_MSG_UNWRAP_NO_VAL_FOR_MAYBE: string;
export declare const ERR_MSG_DEFAULT_VALUE_MUST_NOT_BE_NO_VAL_FOR_MAYBE: string;
export declare const ERR_MSG_RECOVERER_MUST_NOT_RETURN_NO_VAL_FOR_MAYBE: string;