40 lines
885 B
Rust
40 lines
885 B
Rust
use std::marker::PhantomData;
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fn a() {
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WrongImpl::foo(0i32);
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//~^ ERROR the function or associated item `foo` exists for struct `SafeImpl<_, RawImpl<_>>`, but its trait bounds were not satisfied
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//~| ERROR the trait bound `RawImpl<_>: Raw<_>` is not satisfied
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}
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fn b() {
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WrongImpl::<()>::foo(0i32);
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//~^ ERROR the trait bound `RawImpl<()>: Raw<()>` is not satisfied
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//~| ERROR trait bounds were not satisfied
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}
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fn c() {
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CorrectImpl::foo(0i32);
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}
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pub trait Raw<T: ?Sized> {
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type Value;
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}
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pub type WrongImpl<T> = SafeImpl<T, RawImpl<T>>;
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pub type CorrectImpl<T> = SafeImpl<[T], RawImpl<T>>;
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pub struct RawImpl<T>(PhantomData<T>);
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impl<T> Raw<[T]> for RawImpl<T> {
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type Value = T;
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}
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pub struct SafeImpl<T: ?Sized, A: Raw<T>>(PhantomData<(A, T)>);
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impl<T: ?Sized, A: Raw<T>> SafeImpl<T, A> {
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pub fn foo(value: A::Value) {}
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}
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fn main() {}
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