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// Test that we correctly infer variance for region parameters in
// case that involve multiple intricate types.
// Try enums too.
#![feature(rustc_attrs)]
#[rustc_variance]
enum Base<'a, 'b, 'c:'b, 'd> { //~ ERROR ['a: -, 'b: +, 'c: o, 'd: *]
//~^ ERROR: `'d` is never used
Test8A(extern "Rust" fn(&'a isize)),
Test8B(&'b [isize]),
Test8C(&'b mut &'c str),
}
#[rustc_variance]
struct Derived1<'w, 'x:'y, 'y, 'z> { //~ ERROR ['w: *, 'x: o, 'y: +, 'z: -]
//~^ ERROR: `'w` is never used
f: Base<'z, 'y, 'x, 'w>
}
#[rustc_variance] // Combine - and + to yield o
struct Derived2<'a, 'b:'a, 'c> { //~ ERROR ['a: o, 'b: o, 'c: *]
//~^ ERROR: `'c` is never used
f: Base<'a, 'a, 'b, 'c>
}
#[rustc_variance] // Combine + and o to yield o (just pay attention to 'a here)
struct Derived3<'a:'b, 'b, 'c> { //~ ERROR ['a: o, 'b: +, 'c: *]
//~^ ERROR: `'c` is never used
f: Base<'a, 'b, 'a, 'c>
}
#[rustc_variance] // Combine + and * to yield + (just pay attention to 'a here)
struct Derived4<'a, 'b, 'c:'b> { //~ ERROR ['a: -, 'b: +, 'c: o]
f: Base<'a, 'b, 'c, 'a>
}
fn main() {}
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