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//@ 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() {}
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