Add impl for Board

src/main.rs

@@ -8,42 +8,50 @@ struct Board {
     board: [Square; 9],
 }
 
-fn square_to_char(s: &Square) -> char {
-    match s {
-        Square::Empty => '.',
-        Square::Cross => 'X',
-        Square::Circle => 'O',
+impl Board {
+    /// Creates a new empty board
+    fn new() -> Self {
+        Self {
+            board: [
+                Square::Empty,
+                Square::Cross,
+                Square::Circle,
+                Square::Empty,
+                Square::Empty,
+                Square::Empty,
+                Square::Empty,
+                Square::Empty,
+                Square::Empty,
+            ],
         }
     }
 
-fn display(board: Board) {
+    /// Display the board to standard output
+    fn display(&self) {
         for row in 0..3 {
             println!(
                 " {} | {} | {}",
-            square_to_char(&board.board[row * 3]),
-            square_to_char(&board.board[row * 3 + 1]),
-            square_to_char(&board.board[row * 3 + 2])
+                square_to_char(&self.board[row * 3]),
+                square_to_char(&self.board[row * 3 + 1]),
+                square_to_char(&self.board[row * 3 + 2])
             );
             if row == 0 || row == 1 {
                 println!("---+---+---");
             }
         }
     }
+}
+
+fn square_to_char(s: &Square) -> char {
+    match s {
+        Square::Empty => '.',
+        Square::Cross => 'X',
+        Square::Circle => 'O',
+    }
+}
 
 fn main() {
-    let board = Board {
-        board: [
-            Square::Empty,
-            Square::Cross,
-            Square::Circle,
-            Square::Empty,
-            Square::Empty,
-            Square::Empty,
-            Square::Empty,
-            Square::Empty,
-            Square::Empty,
-        ],
-    };
+    let board = Board::new();
 
-    display(board);
+    board.display();
 }