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