extern int oprange(struct empobj *);
extern int in_oparea(struct empobj *, coord, coord);
extern int cando(int, int);
-extern int air_defense(coord, coord, natid, struct emp_qelem *,
- struct emp_qelem *);
/* move.c */
extern int check_lmines(coord, coord, double);
extern int move_ground(struct sctstr *, struct sctstr *,