41 lines
656 B
Rust
41 lines
656 B
Rust
// run-pass
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// Test that we can coerce an `@Object` to an `&Object`
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trait Foo {
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fn foo(&self) -> usize;
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fn bar(&mut self) -> usize;
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}
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impl Foo for usize {
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fn foo(&self) -> usize {
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*self
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}
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fn bar(&mut self) -> usize {
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*self += 1;
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*self
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}
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}
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fn do_it_mut(obj: &mut dyn Foo) {
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let x = obj.bar();
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let y = obj.foo();
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assert_eq!(x, y);
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do_it_imm(obj, y);
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}
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fn do_it_imm(obj: &dyn Foo, v: usize) {
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let y = obj.foo();
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assert_eq!(v, y);
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}
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pub fn main() {
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let mut x: usize = 22;
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let obj = &mut x as &mut dyn Foo;
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do_it_mut(obj);
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do_it_imm(obj, 23);
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do_it_mut(obj);
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}
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