-template<class T> constexpr const T& clamp(const T& v, const T& lo, const T& hi) {
- return v < lo ? lo : v > hi ? hi : v;
+/// safe_destination() returns the bitboard of target square for the given step
+/// from the given square. If the step is off the board, returns empty bitboard.
+
+inline Bitboard safe_destination(Square s, int step)
+{
+ Square to = Square(s + step);
+ return is_ok(to) && distance(s, to) <= 2 ? square_bb(to) : Bitboard(0);
+}
+
+
+/// attacks_bb(Square) returns the pseudo attacks of the give piece type
+/// assuming an empty board.
+
+template<PieceType Pt>
+inline Bitboard attacks_bb(Square s) {
+
+ assert((Pt != PAWN) && (is_ok(s)));
+
+ return PseudoAttacks[Pt][s];