| A non-root module tried to import macros from another crate. |
| |
| Example of erroneous code: |
| |
| ```compile_fail,E0468 |
| mod foo { |
| #[macro_use(debug_assert)] // error: must be at crate root to import |
| extern crate core; // macros from another crate |
| fn run_macro() { debug_assert!(true); } |
| } |
| ``` |
| |
| Only `extern crate` imports at the crate root level are allowed to import |
| macros. |
| |
| Either move the macro import to crate root or do without the foreign macros. |
| This will work: |
| |
| ``` |
| #[macro_use(debug_assert)] // ok! |
| extern crate core; |
| |
| mod foo { |
| fn run_macro() { debug_assert!(true); } |
| } |
| # fn main() {} |
| ``` |
