derived constructors bug

.gitignore

@@ -0,0 +1,2 @@
+*.out
+.vscode/

Bitboard.cpp

@@ -1,7 +1,7 @@
 #include "bitboard.hpp"
 
 
-Bitboard::Bitboard(U64 dec){
+Bitboard::Bitboard(U64 dec) {
     bb = dec;
 }
 
@@ -10,7 +10,7 @@ int Bitboard::BitScanForward() {
 	 * returns the index of LSB between [0,63]
 	 * adapted by CPW, original by @author Kim Walisch (2012)
 	 */
-	if (!bb) throw "empty bitboard";
+	if (!bb) throw empty_bitboard();
     const int index64[64] = {
    		 0, 47,  1, 56, 48, 27,  2, 60,
    		57, 49, 41, 37, 28, 16,  3, 61,
@@ -26,7 +26,7 @@ int Bitboard::BitScanForward() {
     return index64[((bb ^ (bb-1)) * debruijn64) >> 58];
 }
 
-void Bitboard::printNumber() {
+void Bitboard::printNumber() const{
     std::cout << bb;
     return;
 }
@@ -43,25 +43,24 @@ std::ostream& operator<<(std::ostream &out, const Bitboard board){
     return out;
 }
 
-bool Bitboard::empty() {
+bool Bitboard::empty() const {
     return bb == 0;
 }
 
-Bitboard Bitboard::getComplement() {
+Bitboard Bitboard::getComplement() const {
     return Bitboard(~bb);
 }
 
 void Bitboard::bitToggle(int index) {
     bb ^= (1ULL << index);
     return ;
 }
-std::list<int> Bitboard::extractIndexes() {
+std::list<int> Bitboard::extractIndexes() const {
+    Bitboard temp = *this;
     std::list<int> myList;
-	while (bb) {
-		myList.push_back(Bitboard::BitScanForward());
-		bb &= bb-1; //reset LSB
+	while (temp.bb) {
+		myList.push_back(temp.BitScanForward());
+		temp.bb &= temp.bb-1; //reset LSB
 	}
 	return myList;
 }
-
-

bitboard.hpp

@@ -1,6 +1,7 @@
 #include <iostream>
 #include <list>
 #include <string>
+#include <exception>
 
 typedef unsigned long long int U64;  
 #define C64(constantU64) constantU64##ULL 
@@ -15,15 +16,17 @@ class Bitboard {
         friend std::ostream& operator<<(std::ostream &out, Bitboard bit); //prints as chessboard
         void printNumber() const;                                               //prints number
         bool empty() const;
+        int BitScanForward();
     protected:
         U64 bb; //bitboard 64bit
-        int BitScanForward();
         static const U64 notAFile = 0xfefefefefefefefe;
         static const U64 notHFile = 0x7f7f7f7f7f7f7f7f;
         static const U64 notABFile = 0xFCFCFCFCFCFCFCFC;
         static const U64 notGHFile = 0x3F3F3F3F3F3F3F3F;
+        static const U64 firstRank = (1ULL << 8)-1; 
         static const U64 secondRank =  (1ULL << 16)-1;
         static const U64 eighthRank =   (1ULL << 63)-1;
+        class empty_bitboard : public std::exception {};
 };
 
 class BitboardPawns : public Bitboard { //protected or public ??
@@ -63,15 +66,16 @@ class BitboardRooks : public Bitboard {
         Bitboard RookMoves(int index, Bitboard occupiedBitboard); //check if we include last blocker
     protected:
         enum rookDirection {north, south, west, east}; //??
-        U64 rookRays[4][64]; //rays[direction][index]  -  possible moves when chessboard is empty
+        static U64 rookRays[4][64]; //rays[direction][index]  -  possible moves when chessboard is empty
+        void initializeRookRays();
 };
 
 class BitboardBishops : public Bitboard {
     public:
         Bitboard BishopMoves(int index, Bitboard occupiedBitboard); //check if we include last blocker
     protected:
         enum bishopDirection {northWest, southWest, northEast, southEast}; //??
-        U64 bishopRays[4][64]; //rays[direction][index]  -  possible moves when chessboard is empty    
+        static U64 bishopRays[4][64]; //rays[direction][index]  -  possible moves when chessboard is empty    
 };
 
 class BitboardQueens : public BitboardRooks, public BitboardBishops {