41 lines
709 B
Rust
41 lines
709 B
Rust
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// compile-pass
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use std::marker::PhantomData;
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struct Meta<A> {
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value: i32,
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type_: PhantomData<A>
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}
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trait MetaTrait {
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fn get_value(&self) -> i32;
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}
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impl<A> MetaTrait for Meta<A> {
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fn get_value(&self) -> i32 { self.value }
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}
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trait Bar {
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fn get_const(&self) -> &dyn MetaTrait;
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}
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struct Foo<A> {
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_value: A
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}
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impl<A: 'static> Foo<A> {
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const CONST: &'static dyn MetaTrait = &Meta::<Self> {
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value: 10,
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type_: PhantomData
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};
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}
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impl<A: 'static> Bar for Foo<A> {
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fn get_const(&self) -> &dyn MetaTrait { Self::CONST }
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}
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fn main() {
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let foo = Foo::<i32> { _value: 10 };
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let bar: &dyn Bar = &foo;
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println!("const {}", bar.get_const().get_value());
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}
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