error[E0599]: `bool` is not an iterator
  --> ui_tests/export_mod_raw_return.rs:12:33
   |
9  | #[export_module]
   | ---------------- in this procedural macro expansion
...
12 | pub fn test_fn(input: Point) -> bool {
   |                                 ^^^^ `bool` is not an iterator
   |
   = note: the following trait bounds were not satisfied:
           `bool: std::iter::Iterator`
           which is required by `&mut bool: std::iter::Iterator`
   = note: this error originates in the attribute macro `export_module` (in Nightly builds, run with -Z macro-backtrace for more info)