Use consteval and constexpr in more places

engine/src/CMakeLists.txt

@@ -1,6 +1,6 @@
 add_library(wisdom-chess-core STATIC
         board.cpp board.hpp
-        board_builder.cpp board_builder.hpp
+        board_builder.hpp
         board_code.cpp board_code.hpp
         check.cpp check.hpp
         coord.cpp coord.hpp

engine/src/board.cpp

@@ -11,7 +11,7 @@ namespace wisdom
     static constexpr int Board_Length_In_Chars = 31;
 
     Board::Board()
-        : Board { BoardBuilder::fromDefaultPosition() }
+        : Board { default_board_builder }
     {
     }
 
@@ -136,7 +136,7 @@ namespace wisdom
         auto convert = [color](char ch) -> char
         {
             return color == Color::Black 
-                ? gsl::narrow_cast<char> (tolower (ch)) 
+                ? narrow_cast<char> (tolower (ch))
                 : ch;
         };
 
@@ -175,9 +175,9 @@ namespace wisdom
                         row_string += std::to_string (none_count);
 
                     none_count = 0;
-                    char ch = gsl::narrow_cast<char> (toupper (pieceChar (piece)));
+                    char ch = narrow_cast<char> (toupper (pieceChar (piece)));
                     if (pieceColor (piece) == Color::Black)
-                        ch = gsl::narrow_cast<char> (tolower (ch));
+                        ch = narrow_cast<char> (tolower (ch));
 
                     row_string.append (1, ch);
                 }
@@ -268,7 +268,7 @@ namespace wisdom
             for (int8_t source_col = 0; source_col < Num_Columns; source_col++)
             {
                 int8_t first_source_row = 0;
-                auto last_source_row = gsl::narrow<int8_t> (Num_Rows - 1);
+                auto last_source_row = narrow<int8_t> (Num_Rows - 1);
 
                 removeInvalidPawns (result, first_source_row, source_col, result.my_squares);
                 removeInvalidPawns (result, last_source_row, source_col, result.my_squares);
@@ -304,7 +304,7 @@ namespace wisdom
             coord_end, 
             finder
         );
-        auto diff = gsl::narrow<int> (result - coord_begin);
+        auto diff = narrow<int> (result - coord_begin);
 
         return (result != coord_end) 
             ? std::make_optional<Coord> (Coord::fromIndex (diff)) 

engine/src/board.hpp

@@ -251,7 +251,7 @@ namespace wisdom
     constexpr auto coordColor (Coord coord) -> Color
     {
         int parity = (coord.row() % 2 + coord.column() % 2) % 2;
-        return colorFromColorIndex (gsl::narrow_cast<int8_t> (parity));
+        return colorFromColorIndex (narrow_cast<int8_t> (parity));
     }
 
     // white moves up (-)
@@ -262,6 +262,6 @@ namespace wisdom
         static_assert (std::is_integral_v<IntegerType>);
         assert (color == Color::Black || color == Color::White);
         int8_t color_as_int = toInt8 (color);
-        return gsl::narrow_cast<IntegerType> (-1 + 2 * (color_as_int - 1));
+        return narrow_cast<IntegerType> (-1 + 2 * (color_as_int - 1));
     }
 }