fix: actually finish challeng #2(ch.6)

I didn't implement the scanner and the printer lol

src/printer.rs

@@ -12,6 +12,16 @@ pub fn pretty_print(expr: &Expr) -> String {
             None => "None".to_string(),
         },
         Expr::Unary { op, right } => parenthesize(&op.lexeme, &[right]),
+        Expr::Ternary {
+            first,
+            first_op,
+            second,
+            second_op,
+            third,
+        } => parenthesize(
+            &format!("{}{}", first_op.lexeme, second_op.lexeme),
+            &[first, second, third],
+        ),
     }
 }
 

src/scanner.rs

@@ -99,6 +99,8 @@ impl Scanner {
             '<' => self.add_token(TokenType::Less),
             '>' if self.peek_and_match('=') => self.add_token(TokenType::GreaterEqual),
             '>' => self.add_token(TokenType::Greater),
+            '?' => self.add_token(TokenType::Question),
+            ':' => self.add_token(TokenType::Colon),
             // checking for comments and just advance the iterator if it's a comment
             '/' if self.peek_and_match('/') => {
                 while self.peek().is_some_and(|x| x != '\n') {