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// SPDX-License-Identifier: Apache-2.0 OR MIT
#![allow(clippy::disallowed_names)]
use pin_init::*;
#[pin_data]
struct SelfRef {
#[uses('_: invariant)]
not_cov: Box<dyn Fn(&'str str) -> bool + 'str>,
part: &'str str,
str: String,
mut_part: &'mut_str mut str,
#[borrowed(mut)]
mut_str: String,
}
fn use_self_ref() {
stack_pin_init!(let foo = pin_init!(SelfRef {
str: "hello world".to_owned(),
part: &str[..5],
mut_str: "hello world".to_owned(),
mut_part: &mut mut_str[..5],
not_cov: Box::new(move |s| s == str),
}));
// Access via projection.
println!("{}", foo.as_mut().project().part);
// Access via accessor.
println!("{}", foo.part());
// Access via `with_project`, gives mutable reference.
foo.as_mut().with_project(|proj| {
*proj.part = &proj.str[5..];
});
println!("{}", foo.part());
// Access fields that mutable borrow others are similar to those of shared borrow.
println!("{}", foo.as_mut().project().mut_part);
println!("{}", foo.mut_part());
foo.as_mut().with_project(|proj| {
proj.mut_part.make_ascii_uppercase();
});
// Access non-covariant type using `with_` accessor.
foo.with_not_cov(|not_cov| {
not_cov("");
});
// Access non-covariant type using `with_project`.
foo.as_mut().with_project(|proj| (proj.not_cov)(proj.str));
}
fn main() {
use_self_ref();
}
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