Tokens - Address ('@') token for loop labels

src/scanner.rs

@@ -87,6 +87,7 @@ impl Scanner {
             '+' => self.add_token(TokenType::Plus),
             ';' => self.add_token(TokenType::Semicolon),
             '*' => self.add_token(TokenType::Star),
+            '@' => self.add_token(TokenType::Address),
             // Slash is a special case as it may be a line comment
             '/' => {
                 if self.is_match('/') {

src/tokens.rs

@@ -5,6 +5,7 @@ pub enum TokenType {
     RightParen,
     LeftBrace,
     RightBrace,
+    Address,
     Comma,
     Dot,
     Minus,