vocabulary update

src/board.rs

@@ -3,28 +3,29 @@
 use crate::bitboard::*;
 
 macro_rules! container {
-    ($a:ident, $b:ident, $n:literal) => {
+    ($v:vis, $a:ident, $b:ident, $n:literal) => {
         #[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
-        pub(crate) struct $b<T>(pub(crate) [T; $n]);
+        $v struct $b<T>(pub(crate) [T; $n]);
         #[allow(unused)]
         impl<T> $b<T> {
             #[inline]
-            pub fn new<F>(f: F) -> Self
+            pub const fn new(values: [T; $n]) -> Self {
+                Self(values)
+            }
+            #[inline]
+            pub fn with<F>(f: F) -> Self
             where
                 F: FnMut($a) -> T,
             {
                 Self($a::all().map(f))
             }
             #[inline]
-            pub fn get(&self, k: $a) -> &T {
-                unsafe { self.0.get_unchecked(k as usize) }
+            pub const fn get(&self, k: $a) -> &T {
+                &self.0[k as usize]
             }
             #[inline]
-            pub fn get_mut(&mut self, k: $a) -> &mut T {
-                unsafe { self.0.get_unchecked_mut(k as usize) }
-            }
-            pub(crate) const fn get_const(&self, k: $a) -> &T {
-                &self.0[k as usize]
+            pub const fn get_mut(&mut self, k: $a) -> &mut T {
+                &mut self.0[k as usize]
             }
         }
     };
@@ -38,11 +39,11 @@ pub enum Color {
     Black,
 }
 
-container!(Color, ByColor, 2);
+container!(pub, Color, ByColor, 2);
 
 impl Color {
     #[inline]
-    pub fn all() -> [Self; 2] {
+    pub const fn all() -> [Self; 2] {
         [Self::White, Self::Black]
     }
 
@@ -96,11 +97,11 @@ pub enum File {
     H,
 }
 
-container!(File, ByFile, 8);
+container!(pub(crate), File, ByFile, 8);
 
 impl File {
     #[inline]
-    pub fn all() -> [Self; 8] {
+    pub const fn all() -> [Self; 8] {
         [
             Self::A,
             Self::B,
@@ -114,37 +115,55 @@ impl File {
     }
 
     #[inline]
-    pub fn to_char(self) -> char {
-        self.to_ascii() as char
+    pub const fn new(index: u8) -> Option<Self> {
+        if index < 8 {
+            Some(unsafe { Self::new_unchecked(index) })
+        } else {
+            None
+        }
     }
 
     #[inline]
-    pub fn from_char(file: char) -> Option<Self> {
-        u8::try_from(file).ok().and_then(Self::from_ascii)
+    pub const unsafe fn new_unchecked(index: u8) -> Self {
+        debug_assert!(index < 8);
+        std::mem::transmute(index)
     }
 
     #[inline]
-    pub(crate) fn to_ascii(self) -> u8 {
+    pub const fn to_ascii(self) -> u8 {
         self as u8 + b'a'
     }
 
     #[inline]
-    pub(crate) fn from_ascii(c: u8) -> Option<Self> {
-        (c <= b'h')
-            .then(|| c.checked_sub(b'a').map(|i| unsafe { Self::transmute(i) }))
-            .flatten()
+    pub const fn from_ascii(c: u8) -> Option<Self> {
+        if c <= b'h' {
+            match c.checked_sub(b'a') {
+                Some(i) => Some(unsafe { Self::new_unchecked(i) }),
+                None => None,
+            }
+        } else {
+            None
+        }
+    }
+
+    #[inline]
+    pub const fn to_char(self) -> char {
+        self.to_ascii() as char
+    }
+
+    #[inline]
+    pub const fn from_char(file: char) -> Option<Self> {
+        if file as u32 <= 255 {
+            Self::from_ascii(file as u8)
+        } else {
+            None
+        }
     }
 
     #[inline]
     pub(crate) const fn bitboard(self) -> Bitboard {
         Bitboard(0x0101010101010101 << (self as u8))
     }
-
-    #[inline]
-    pub(crate) const unsafe fn transmute(value: u8) -> Self {
-        debug_assert!(value < 8);
-        std::mem::transmute(value)
-    }
 }
 
 impl std::fmt::Display for File {
@@ -168,11 +187,11 @@ pub enum Rank {
     Eighth,
 }
 
-container!(Rank, ByRank, 8);
+container!(pub(crate), Rank, ByRank, 8);
 
 impl Rank {
     #[inline]
-    pub fn all() -> [Self; 8] {
+    pub const fn all() -> [Self; 8] {
         [
             Self::First,
             Self::Second,
@@ -186,42 +205,60 @@ impl Rank {
     }
 
     #[inline]
-    pub fn to_char(self) -> char {
-        self.to_ascii() as char
+    pub const fn new(index: u8) -> Option<Self> {
+        if index < 8 {
+            Some(unsafe { Self::new_unchecked(index) })
+        } else {
+            None
+        }
     }
 
     #[inline]
-    pub fn from_char(rank: char) -> Option<Self> {
-        u8::try_from(rank).ok().and_then(Self::from_ascii)
+    pub const unsafe fn new_unchecked(index: u8) -> Self {
+        debug_assert!(index < 8);
+        std::mem::transmute(index)
     }
 
     #[inline]
-    pub fn mirror(self) -> Self {
-        unsafe { Self::transmute(!(self as u8)) }
-    }
-
-    #[inline]
-    pub(crate) fn to_ascii(self) -> u8 {
+    pub const fn to_ascii(self) -> u8 {
         self as u8 + b'1'
     }
 
     #[inline]
-    pub(crate) fn from_ascii(c: u8) -> Option<Self> {
-        (c <= b'8')
-            .then(|| c.checked_sub(b'1').map(|i| unsafe { Self::transmute(i) }))
-            .flatten()
+    pub const fn from_ascii(c: u8) -> Option<Self> {
+        if c <= b'8' {
+            match c.checked_sub(b'1') {
+                Some(i) => Some(unsafe { Self::new_unchecked(i) }),
+                None => None,
+            }
+        } else {
+            None
+        }
+    }
+
+    #[inline]
+    pub const fn to_char(self) -> char {
+        self.to_ascii() as char
+    }
+
+    #[inline]
+    pub const fn from_char(rank: char) -> Option<Self> {
+        if rank as u32 <= 255 {
+            Self::from_ascii(rank as u8)
+        } else {
+            None
+        }
+    }
+
+    #[inline]
+    pub const fn mirror(self) -> Self {
+        unsafe { Self::new_unchecked(!(self as u8)) }
     }
 
     #[inline]
     pub(crate) const fn bitboard(self) -> Bitboard {
         Bitboard(0xFF << ((self as u64) << 3))
     }
-
-    #[inline]
-    pub(crate) const unsafe fn transmute(value: u8) -> Self {
-        debug_assert!(value < 8);
-        std::mem::transmute(value)
-    }
 }
 
 impl std::fmt::Display for Rank {
@@ -246,12 +283,12 @@ pub enum Square{
     A8, B8, C8, D8, E8, F8, G8, H8,
 }
 
-container!(Square, BySquare, 64);
+container!(pub, Square, BySquare, 64);
 
 impl Square {
     #[inline]
     #[rustfmt::skip]
-    pub fn all() -> [Self; 64] {
+    pub const fn all() -> [Self; 64] {
         [
             Self::A1, Self::B1, Self::C1, Self::D1, Self::E1, Self::F1, Self::G1, Self::H1,
             Self::A2, Self::B2, Self::C2, Self::D2, Self::E2, Self::F2, Self::G2, Self::H2,
@@ -282,22 +319,22 @@ impl Square {
     }
 
     #[inline]
-    pub fn from_coords(file: File, rank: Rank) -> Self {
+    pub const fn from_coords(file: File, rank: Rank) -> Self {
         unsafe { Self::new_unchecked(((rank as u8) << 3) | file as u8) }
     }
 
     #[inline]
     pub const fn file(self) -> File {
-        unsafe { File::transmute((self as u8) & 7) }
+        unsafe { File::new_unchecked((self as u8) & 7) }
     }
 
     #[inline]
     pub const fn rank(self) -> Rank {
-        unsafe { Rank::transmute((self as u8) >> 3) }
+        unsafe { Rank::new_unchecked((self as u8) >> 3) }
     }
 
     #[inline]
-    pub fn mirror(self) -> Self {
+    pub const fn mirror(self) -> Self {
         let sq = self as u8;
         unsafe { Self::new_unchecked(sq & 0b000111 | (!sq & 0b111000)) }
     }
@@ -465,7 +502,7 @@ pub enum Role {
 
 impl Role {
     #[inline]
-    pub fn all() -> [Self; 6] {
+    pub const fn all() -> [Self; 6] {
         [
             Self::Pawn,
             Self::Knight,
@@ -521,11 +558,11 @@ impl Role {
 }
 
 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
-pub(crate) struct ByRole<T>(pub(crate) [T; 6]);
+pub struct ByRole<T>(pub(crate) [T; 6]);
 #[allow(unused)]
 impl<T> ByRole<T> {
     #[inline]
-    pub fn new<F>(f: F) -> Self
+    pub fn with<F>(f: F) -> Self
     where
         F: FnMut(Role) -> T,
     {
@@ -533,13 +570,22 @@ impl<T> ByRole<T> {
     }
 
     #[inline]
-    pub fn get(&self, kind: Role) -> &T {
-        unsafe { self.0.get_unchecked((kind as usize).unchecked_sub(1)) }
+    pub const fn new(values: [T; 6]) -> Self {
+        Self(values)
     }
 
     #[inline]
-    pub fn get_mut(&mut self, kind: Role) -> &mut T {
-        unsafe { self.0.get_unchecked_mut((kind as usize).unchecked_sub(1)) }
+    pub const fn get(&self, role: Role) -> &T {
+        let i = unsafe { (role as usize).unchecked_sub(1) };
+        unsafe { std::hint::assert_unchecked(i < 6) };
+        &self.0[i]
+    }
+
+    #[inline]
+    pub const fn get_mut(&mut self, role: Role) -> &mut T {
+        let i = unsafe { (role as usize).unchecked_sub(1) };
+        unsafe { std::hint::assert_unchecked(i < 6) };
+        &mut self.0[i]
     }
 }
 
@@ -574,7 +620,7 @@ where
 }
 
 /// A chess piece (i.e. its [`Role`] and [`Color`]).
-#[derive(Debug, Clone, Copy, PartialEq, Eq, Hash)]
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub struct Piece {
     pub role: Role,
     pub color: Color,
@@ -593,7 +639,7 @@ pub(crate) enum Direction {
     West,
 }
 
-container!(Direction, ByDirection, 8);
+container!(pub(crate), Direction, ByDirection, 8);
 
 impl Direction {
     #[inline]
@@ -644,7 +690,7 @@ pub enum CastlingSide {
     Long,
 }
 
-container!(CastlingSide, ByCastlingSide, 2);
+container!(pub(crate), CastlingSide, ByCastlingSide, 2);
 
 impl CastlingSide {
     #[inline]