Bound

A minimal crate to encapsulate the act of deriving a struct from a reference. Notably useful for wrapping LockGuard instances obtained from Arc<RwLock<T>> for example, but essentially works with anything that has a similar relation as the LockGuard does to the RwLock.

Usage

This and all other examples are also available on https:://docs.rs/bound

use std::sync::{Arc, RwLock};
use bound::Bound;

let shared = Arc::new(RwLock::new(1));
let mut writer = Bound::try_new(shared.clone(), |a| a.write()).expect("Failed to lock");
*writer = 2;

// writer now has the following type
type Writer = Bound<RwLockWriteGuard<'static, usize>, Arc<RwLock<usize>>>

You can now safely pass writer around and put it in structs, something you couldn't do with an RwLockWriteGuard by default because it's derived from the local reference to its lock.