49 lines
541 B
Rust
49 lines
541 B
Rust
// run-pass
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#![feature(trait_upcasting)]
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trait A {
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fn foo_a(&self);
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}
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trait B {
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fn foo_b(&self);
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}
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trait C: A + B {
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fn foo_c(&self);
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}
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struct S(i32);
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impl A for S {
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fn foo_a(&self) {
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unreachable!();
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}
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}
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impl B for S {
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fn foo_b(&self) {
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assert_eq!(42, self.0);
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}
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}
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impl C for S {
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fn foo_c(&self) {
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unreachable!();
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}
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}
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fn invoke_inner(b: &dyn B) {
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b.foo_b();
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}
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fn invoke_outer(c: &dyn C) {
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invoke_inner(c);
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}
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fn main() {
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let s = S(42);
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invoke_outer(&s);
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}
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