// check-pass // aux-build:my_crate.rs // aux-build:unhygienic_example.rs #![feature(decl_macro)] extern crate unhygienic_example; extern crate my_crate; // (b) // Hygienic version of `unhygienic_macro`. pub macro hygienic_macro() { fn g() {} // (c) ::unhygienic_example::unhygienic_macro!(); // ^ Even though we invoke an unhygienic macro, `hygienic_macro` remains hygienic. // In the above expansion: // (1) `my_crate` always resolves to (b) regardless of invocation site. // (2) The defined function `f` is only usable inside this macro definition. // (3) `g` always resolves to (c) regardless of invocation site. // (4) `$crate::g` remains hygienic and continues to resolve to (a). f(); } #[allow(unused)] fn test_hygienic_macro() { hygienic_macro!(); fn f() {} // (d) no conflict f(); // resolves to (d) } fn main() {}