51 lines
1.1 KiB
Rust
51 lines
1.1 KiB
Rust
// check-pass
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#![feature(staged_api)]
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#![feature(const_trait_impl)]
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#![feature(const_t_try)]
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#![feature(const_try)]
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#![feature(try_trait_v2)]
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#![stable(feature = "foo", since = "1.0")]
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use std::ops::{ControlFlow, FromResidual, Try};
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#[stable(feature = "foo", since = "1.0")]
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pub struct T;
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#[stable(feature = "foo", since = "1.0")]
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#[rustc_const_unstable(feature = "const_t_try", issue = "none")]
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impl const Try for T {
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type Output = T;
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type Residual = T;
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fn from_output(t: T) -> T {
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t
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}
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fn branch(self) -> ControlFlow<T, T> {
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ControlFlow::Continue(self)
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}
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}
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#[stable(feature = "foo", since = "1.0")]
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#[rustc_const_unstable(feature = "const_t_try", issue = "none")]
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impl const FromResidual for T {
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fn from_residual(t: T) -> T {
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t
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}
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}
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#[stable(feature = "foo", since = "1.0")]
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#[const_trait]
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pub trait Tr {
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#[stable(feature = "foo", since = "1.0")]
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fn bar() -> T {
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T?
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// Should be allowed.
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// Must enable unstable features to call this trait fn in const contexts.
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}
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}
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fn main() {}
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