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//@ compile-flags: --edition 2018
#![feature(try_blocks)]
#[inline(never)]
fn do_something_with<T>(_x: T) {}
// This test checks that borrows made and returned inside try blocks are properly constrained
pub fn main() {
{
// Test that a borrow which *might* be returned still freezes its referent
let mut i = 222;
let x: Result<&i32, ()> = try {
Err(())?;
&i
};
i = 0; //~ ERROR cannot assign to `i` because it is borrowed
let _ = i;
do_something_with(x);
}
{
let x = String::new();
let _y: Result<(), ()> = try {
Err(())?;
::std::mem::drop(x);
};
println!("{}", x); //~ ERROR borrow of moved value: `x`
}
{
// Test that a borrow which *might* be assigned to an outer variable still freezes
// its referent
let mut i = 222;
let mut j = &-1;
let _x: Result<(), ()> = try {
Err(())?;
j = &i;
};
i = 0; //~ ERROR cannot assign to `i` because it is borrowed
let _ = i;
do_something_with(j);
}
}
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