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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 borrows returned from a try block must be valid for the lifetime of the
// result variable
let result: Result<(), &str> = try {
let my_string = String::from("");
let my_str: & str = & my_string;
//~^ ERROR `my_string` does not live long enough
Err(my_str) ?;
Err("") ?;
};
do_something_with(result);
}
{
// Test that borrows returned from try blocks freeze their referent
let mut i = 5;
let k = &mut i;
let mut j: Result<(), &mut i32> = try {
Err(k) ?;
i = 10; //~ ERROR cannot assign to `i` because it is borrowed
};
::std::mem::drop(k); //~ ERROR use of moved value: `k`
i = 40; //~ ERROR cannot assign to `i` because it is borrowed
let i_ptr = if let Err(i_ptr) = j { i_ptr } else { panic ! ("") };
*i_ptr = 50;
}
}
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