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//@ revisions: current next
//@ ignore-compare-mode-next-solver (explicit revisions)
//@[next] compile-flags: -Znext-solver
#![feature(trait_upcasting)]
trait Foo: Bar<i32> + Bar<u32> {}
trait Bar<T> {
fn bar(&self) -> Option<T> {
None
}
}
fn test_specific(x: &dyn Foo) {
let _ = x as &dyn Bar<i32>; // OK
let _ = x as &dyn Bar<u32>; // OK
}
fn test_unknown_version(x: &dyn Foo) {
let _ = x as &dyn Bar<_>; // Ambiguous
//~^ ERROR non-primitive cast
}
fn test_infer_version(x: &dyn Foo) {
let a = x as &dyn Bar<_>; // OK
let _: Option<u32> = a.bar();
}
fn main() {}
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