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//@ check-pass
//@ edition: 2018
#![feature(never_patterns)]
#![allow(incomplete_features)]
#![deny(unreachable_patterns)]
fn main() {}
enum Void {}
// A never pattern alone diverges.
fn never_arg(!: Void) -> ! {}
fn never_arg_returns_anything<T>(!: Void) -> T {}
fn ref_never_arg(&!: &Void) -> ! {}
fn never_let() -> ! {
let ptr: *const Void = std::ptr::null();
unsafe {
let ! = *ptr;
}
}
fn never_match() -> ! {
let ptr: *const Void = std::ptr::null();
unsafe {
match *ptr { ! };
}
// Ensures this typechecks because of divergence and not the type of the match expression.
println!();
}
// Note: divergence is not detected for async fns when the `!` is in the argument (#120240).
async fn async_let(x: Void) -> ! {
let ! = x;
}
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