borrowed-thread

thread-safe way to pass borrow to thread::spawn

examples

with &mut

```rust

use borrowed_thread;

let mut owned = "ABC".to_owned();

let borrowedhandle = borrowedthread::spawn(|| { owned.push('D'); 0 });

let ret = borrowed_handle.join().expect("join err");

asserteq!(0, ret); asserteq!("ABCD", owned); ```

with &

```rust

use borrowed_thread;

let owned = "ABC".to_owned();

let borrowedhandle = borrowedthread::spawn(|| { assert_eq!("ABC", owned); 0 });

let ret = borrowed_handle.join().expect("join err");

assert_eq!(0, ret); ```

panic when drop without join

```rust

let mut owned = "ABC".to_owned();

let borrowed_handle = super::spawn(|| { owned.push('D'); 0 });

// this will cause panic! drop(borrowed_handle);

assert_eq!("ABCD", owned); ```