message: fix
  It's not rust code..
diff: @@ -540,6 +540,7 @@ impl Fold<SeqExpr> for SimplifyExpr {
  /// Folds 'typeof(foo)' if foo is a literal, e.g.
  ///
  /// typeof("bar") --> "string"
  +///
  /// typeof(6) --> "number"
  fn try_fold_typeof(UnaryExpr { span, op, arg }: UnaryExpr) -> Expr {
  assert_eq!(op, op!("typeof"));
  