typing improvements

src/repr/bitboard.rs

@@ -12,7 +12,7 @@ pub type BitBoardInner = u64;
 pub struct BitBoard(BitBoardInner);
 
 // BitBoard should be big enough to fit all points on the board
-const_assert!(std::mem::size_of::<BitBoard>() * 8 >= Board::BOARD_AREA as usize);
+const_assert!(std::mem::size_of::<BitBoard>() * 8 >= Board::BOARD_AREA.0 as usize);
 
 impl BitBoard {
     #[allow(clippy::new_without_default)]
@@ -38,7 +38,6 @@ impl BitBoard {
         self.0 |= (value as BitBoardInner) << index; // set bit (if needed)
     }
 
-    // works on both `bitvec` and native (const on native)
     pub const fn count(&self) -> usize {
         self.0.count_ones() as usize
     }
@@ -94,7 +93,7 @@ impl BitBoard {
     const fn col_mask(col: CoordAxis) -> Self {
         let mut mask = 0;
         let mut i = 0;
-        while i < Board::BOARD_AREA {
+        while i < Board::BOARD_AREA.0 {
             mask |= 1 << (i + col);
             i += Board::BOARD_SIZE;
         }
@@ -154,7 +153,7 @@ mod test {
     #[test]
     fn set_and_get() {
         let mut b = BitBoard::new();
-        for c in 0..Board::BOARD_AREA {
+        for c in 0..Board::BOARD_AREA.0 {
             assert!(
                 !b.get(CoordPair(c)),
                 "A just-initalized BitBoard should be completely empty"

src/repr/board.rs

@@ -6,13 +6,13 @@ use std::{cmp::Ordering, fmt};
 /// Map of all points on the board against some type T
 /// Used to index like so: example[i][j]
 /// with each coordinate
-pub struct PosMap<T: Default>(ArrayVec<T, { Board::BOARD_AREA as usize }>);
+pub struct PosMap<T: Default>(ArrayVec<T, { Board::BOARD_AREA.0 as usize }>);
 
 impl<T: Default> PosMap<T> {
     #[allow(clippy::new_without_default)]
     pub fn new() -> Self {
         Self(ArrayVec::from_iter(
-            (0..Board::BOARD_AREA).map(|_| Default::default()),
+            (0..Board::BOARD_AREA.0).map(|_| Default::default()),
         ))
     }
 
@@ -117,7 +117,7 @@ impl Board {
     pub const BOARD_SIZE: CoordAxis = 8;
 
     /// Area of the board
-    pub const BOARD_AREA: CoordAxis = Self::BOARD_SIZE.pow(2);
+    pub const BOARD_AREA: CoordPair = CoordPair(CoordPair(Self::BOARD_SIZE).0.pow(2));
 
     /// Create a new empty board
     #[allow(clippy::new_without_default)]
@@ -156,7 +156,7 @@ impl Board {
 
     /// Provides an iterator of all possible positions on the board
     pub fn all_positions() -> impl Iterator<Item = CoordPair> {
-        (0..Self::BOARD_SIZE).flat_map(|i| (0..Self::BOARD_SIZE).map(move |j| (i, j).into()))
+        (0..Self::BOARD_AREA.0).map(CoordPair)
     }
 
     /// Returns an iterator of all possible moves a `color` can make
@@ -248,12 +248,16 @@ impl Board {
         let count = flip_mask.count();
 
         // Apply the flips
-        *self.board_mut(starting_color) |= flip_mask;
+        self.apply_flip_mask(starting_color, flip_mask);
-        *self.board_mut(starting_color.flip()) &= !flip_mask;
 
         count
     }
 
+    fn apply_flip_mask(&mut self, color: Piece, flip_mask: BitBoard) {
+        *self.board_mut(color) |= flip_mask;
+        *self.board_mut(color.flip()) &= !flip_mask;
+    }
+
     /// Propegate piece captures originating from (i, j)
     /// DO NOT USE THIS ALONE, this should be called as a part of
     /// [`Board::place`] or [`Board::place_and_prop_unchecked`]

src/repr/coords.rs

@@ -9,7 +9,7 @@ pub type CoordAxis = u8;
 /// using u8 for this results in a ~3-6% perf increase
 pub type CoordPairInner = u8;
 
-const_assert!(CoordPairInner::MAX as usize >= Board::BOARD_AREA as usize);
+const_assert!(CoordPairInner::MAX as usize >= Board::BOARD_AREA.0 as usize);
 
 #[derive(PartialEq, Eq, Copy, Clone, Hash)]
 pub struct CoordPair(pub CoordPairInner);