-extern struct yx_uint16 mv_yx_in_dir (char d, struct yx_uint16 yx) {
-// Return yx coordinates one step to the direction d of yx.
- if (d == NORTH) yx.y--;
- else if (d == EAST) yx.x++;
- else if (d == SOUTH) yx.y++;
- else if (d == WEST) yx.x--;
- return yx; }