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//@ revisions: e2021 e2024
//
//@[e2021] edition: 2021
//@[e2024] edition: 2024
//
//@[e2021] run-pass
//@[e2021] run-rustfix
//@[e2024] check-fail
fn main() {
m();
q();
let _ = meow();
let _ = fallback_return();
let _ = fully_apit();
}
fn m() {
//[e2021]~^ this function depends on never type fallback being `()`
//[e2021]~| this was previously accepted by the compiler but is being phased out; it will become a hard error in Rust 2024 and in a future release in all editions!
let x: () = match true {
true => Default::default(),
//[e2024]~^ error: the trait bound `!: Default` is not satisfied
false => panic!("..."),
};
dbg!(x);
}
fn q() -> Option<()> {
//[e2021]~^ this function depends on never type fallback being `()`
//[e2021]~| this was previously accepted by the compiler but is being phased out; it will become a hard error in Rust 2024 and in a future release in all editions!
fn deserialize<T: Default>() -> Option<T> {
Some(T::default())
}
deserialize::<()>()?;
//[e2024]~^ error: the trait bound `!: Default` is not satisfied
None
}
// Make sure we turbofish the right argument
fn help<'a: 'a, T: Into<()>, U>(_: U) -> Result<T, ()> {
Err(())
}
fn meow() -> Result<(), ()> {
//[e2021]~^ this function depends on never type fallback being `()`
//[e2021]~| this was previously accepted by the compiler but is being phased out; it will become a hard error in Rust 2024 and in a future release in all editions!
help::<(), _>(1)?;
//[e2024]~^ error: the trait bound `(): From<!>` is not satisfied
Ok(())
}
pub fn takes_apit<T>(_y: impl Fn() -> T) -> Result<T, ()> {
Err(())
}
pub fn fallback_return() -> Result<(), ()> {
//[e2021]~^ this function depends on never type fallback being `()`
//[e2021]~| this was previously accepted by the compiler but is being phased out; it will become a hard error in Rust 2024 and in a future release in all editions!
takes_apit::<()>(|| Default::default())?;
//[e2024]~^ error: the trait bound `!: Default` is not satisfied
Ok(())
}
fn mk<T>() -> Result<T, ()> {
Err(())
}
fn takes_apit2(_x: impl Default) {}
fn fully_apit() -> Result<(), ()> {
//[e2021]~^ this function depends on never type fallback being `()`
//[e2021]~| this was previously accepted by the compiler but is being phased out; it will become a hard error in Rust 2024 and in a future release in all editions!
takes_apit2(mk::<()>()?);
//[e2024]~^ error: the trait bound `!: Default` is not satisfied
Ok(())
}
|
