38 lines
1.1 KiB
Rust
38 lines
1.1 KiB
Rust
//@ 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;
|
|
}
|
|
}
|