[bitboard] Export the bit_scanner module

Clients can access TrailingBitScanner and LeadingBitScanner directly now.

bitboard/src/bit_scanner.rs

@@ -20,7 +20,7 @@ macro_rules! bit_scanner {
 bit_scanner!(LeadingBitScanner);
 bit_scanner!(TrailingBitScanner);
 
-fn _index_to_square(index: usize) -> Square {
+fn index_to_square(index: usize) -> Square {
     unsafe {
         #[allow(clippy::cast_possible_truncation)]
         Square::from_index_unchecked(index as u8)
@@ -49,7 +49,7 @@ impl Iterator for LeadingBitScanner {
         // Shift 1 additional place to account for the 1 that `leading_zeros` found.
         self.shift += leading_zeros + 1;
 
-        Some(_index_to_square(position))
+        Some(index_to_square(position))
     }
 }
 
@@ -75,7 +75,7 @@ impl Iterator for TrailingBitScanner {
         // Shift 1 additional place to account for the 1 that `leading_zeros` found.
         self.shift += trailing_zeros + 1;
 
-        Some(_index_to_square(position))
+        Some(index_to_square(position))
     }
 }
 

bitboard/src/lib.rs

@@ -1,6 +1,7 @@
 // Eryn Wells <eryn@erynwells.me>
 
-mod bit_scanner;
+pub mod bit_scanner;
+
 mod bitboard;
 mod direction;
 mod library;