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#[derive(Debug)]
struct X<T>(T);
impl<T: Clone> Clone for X<T> {
fn clone(&self) -> X<T> {
X(self.0.clone())
}
}
#[derive(Debug)]
struct Y;
#[derive(Debug)]
struct Str {
x: Option<i32>,
}
fn foo(s: &mut Option<i32>) {
if s.is_none() {
*s = Some(0);
}
println!("{:?}", s);
}
fn bar<T: std::fmt::Debug>(s: &mut X<T>) {
println!("{:?}", s);
}
fn main() {
let s = Str { x: None };
let sr = &s;
let mut sm = sr.clone();
foo(&mut sm.x); //~ ERROR cannot borrow `sm.x` as mutable, as it is behind a `&` reference
let x = X(Y);
let xr = &x;
let mut xm = xr.clone();
bar(&mut xm); //~ ERROR cannot borrow data in a `&` reference as mutable
}
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