bool datasheet_put_row (struct datasheet *, casenumber, struct ccase *);
bool datasheet_get_value (const struct datasheet *, casenumber, size_t column,
union value *, int width);
bool datasheet_put_row (struct datasheet *, casenumber, struct ccase *);
bool datasheet_get_value (const struct datasheet *, casenumber, size_t column,
union value *, int width);