Roll back changes from the rewrite branch

src/lexer.rs

@@ -232,7 +232,7 @@ pub fn lexer<'src>() -> impl Parser<
     .map(Token::Keyword);
 
     choice((
-        boolean, float, integer, string, identifier, keyword, control, operator,
+        boolean, float, integer, string, keyword, identifier, control, operator,
     ))
     .map_with(|token, state| (token, state.span()))
     .padded()

tests/functions.rs

@@ -47,7 +47,7 @@ fn callback() {
 
 #[test]
 fn built_in_function_call() {
-    assert_eq!(interpret("output('Hiya')"), Ok(None));
+    assert_eq!(interpret("io.write_line('Hiya')"), Ok(None));
 }
 
 #[test]