void data_out (char *s, const struct fmt_spec *fp, const union value *v);
char *fmt_to_string (const struct fmt_spec *);
void num_to_string (double v, char *s, int w, int d);
void data_out (char *s, const struct fmt_spec *fp, const union value *v);
char *fmt_to_string (const struct fmt_spec *);
void num_to_string (double v, char *s, int w, int d);