mirror of https://github.com/rust-lang/rust
39 lines
792 B
Rust
39 lines
792 B
Rust
trait Cycle: Sized {
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type Next: Cycle<Next = Self>;
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}
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impl<T> Cycle for Box<T> {
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type Next = Vec<T>;
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}
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impl<T> Cycle for Vec<T> {
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type Next = Box<T>;
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}
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trait X<'a, T: Cycle + for<'b> X<'b, T>>
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where
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for<'b> <T as X<'b, T>>::U: Clone,
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for<'b> T::Next: X<'b, T::Next>,
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for<'b> <T::Next as X<'b, T::Next>>::U: Clone,
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{
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type U: ?Sized;
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fn f(x: &<T as X<'_, T>>::U) {
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<<T as X<'_, T>>::U>::clone(x);
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}
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}
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impl<S, T> X<'_, Vec<T>> for S {
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type U = str;
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//~^ ERROR the trait bound `str: Clone` is not satisfied
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}
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impl<S, T> X<'_, Box<T>> for S {
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type U = str;
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//~^ ERROR the trait bound `str: Clone` is not satisfied
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}
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pub fn main() {
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<i32 as X<Box<i32>>>::f("abc");
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//~^ ERROR the trait bound `str: Clone` is not satisfied
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}
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