feat: add support for booleans and comparision operators

src/frontend/lexer.rs

@@ -142,6 +142,11 @@ impl<'src> Lexer<'src> {
             '/' => token!(TokenKind::Slash),
             '%' => token!(TokenKind::Percent),
 
+            '!' => token!(TokenKind::Bang, '=' => TokenKind::Unequal),
+            '=' => token!(TokenKind::Assign, '=' => TokenKind::Equal),
+            '<' => token!(TokenKind::LessThan, '=' => TokenKind::LessEqual),
+            '>' => token!(TokenKind::GreaterThan, '=' => TokenKind::GreaterEqual),
+
             '.' => token!(TokenKind::Dot),
             ',' => token!(TokenKind::Comma),
             ':' => token!(TokenKind::Colon),
@@ -283,4 +288,21 @@ mod test {
             ]
         )
     }
+
+    #[test]
+    fn comparison_and_logical() {
+        assert_eq!(
+            tokenize("== != < <= > >= ! ="),
+            vec![
+                Token::new(TokenKind::Equal, "==", Span::new(0, 2)),
+                Token::new(TokenKind::Unequal, "!=", Span::new(3, 5)),
+                Token::new(TokenKind::LessThan, "<", Span::new(6, 7)),
+                Token::new(TokenKind::LessEqual, "<=", Span::new(8, 10)),
+                Token::new(TokenKind::GreaterThan, ">", Span::new(11, 12)),
+                Token::new(TokenKind::GreaterEqual, ">=", Span::new(13, 15)),
+                Token::new(TokenKind::Bang, "!", Span::new(16, 17)),
+                Token::new(TokenKind::Assign, "=", Span::new(18, 19)),
+            ]
+        )
+    }
 }