44 lines
1.0 KiB
Rust
44 lines
1.0 KiB
Rust
// check-pass
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// edition:2021
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#![allow(unreachable_code)]
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use std::fmt::{self, Display};
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use std::marker::PhantomData;
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struct NotSend {
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marker: PhantomData<*const u8>,
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}
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const NOT_SEND: NotSend = NotSend { marker: PhantomData };
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impl Display for NotSend {
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fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
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formatter.write_str("this value does not implement Send")
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}
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}
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async fn f(_: u8) {}
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// Exercises this matcher in panic_2021:
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// ($($t:tt)+) => $crate::panicking::panic_fmt(...)
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async fn panic_fmt() {
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// Panic returns `!`, so the await is never reached, and in particular the
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// temporaries inside the formatting machinery are not still alive at the
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// await point.
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let todo = "...";
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f(panic!("not yet implemented: {}", todo)).await;
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}
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// Exercises ("{}", $arg:expr) => $crate::panicking::panic_display(&$arg)
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async fn panic_display() {
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f(panic!("{}", NOT_SEND)).await;
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}
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fn require_send(_: impl Send) {}
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fn main() {
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require_send(panic_fmt());
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require_send(panic_display());
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}
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