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//@ run-pass
//! Test that implicit deref patterns interact as expected with `Cow` constructor patterns.
#![feature(deref_patterns)]
#![allow(incomplete_features)]
use std::borrow::Cow;
use std::rc::Rc;
fn main() {
let cow: Cow<'static, [u8]> = Cow::Borrowed(&[1, 2, 3]);
match cow {
[..] => {}
}
match cow {
Cow::Borrowed(_) => {}
Cow::Owned(_) => unreachable!(),
}
match Rc::new(&cow) {
Cow::Borrowed { 0: _ } => {}
Cow::Owned { 0: _ } => unreachable!(),
}
let cow_of_cow: Cow<'_, Cow<'static, [u8]>> = Cow::Owned(cow);
match cow_of_cow {
[..] => {}
}
// This matches on the outer `Cow` (the owned one).
match cow_of_cow {
Cow::Borrowed(_) => unreachable!(),
Cow::Owned(_) => {}
}
match Rc::new(&cow_of_cow) {
Cow::Borrowed { 0: _ } => unreachable!(),
Cow::Owned { 0: _ } => {}
}
}
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