scell

A smart cell for Rust that allows feature gating for disabling runtime-checked borrows and provides a simple interface

The intention of this crate is to allow the use of a Rc<RefCell<T>> throughout code where, after enough testing has been done, the unchecked feature can be enabled, which will convert SCell into a Rc<UnsafeCell<T>>.

SCell provides all of the things that the combination of Rc<RefCell<T>> normally allow and some more, such as implementations for PartialOrd and Ord.

If you plan to do significant testing in debug mode, add the unchecked feature to this crate in release mode. Otherwise, it might be best to enable optimizations in debug so you can test in debug or to create a new profile for testing of optimized binaries that still do the runtime checking that RefCell provides. Once you have performed your testing, use a compile mode with the unchecked feature enabled for this crate and it will remove the overhead from RefCell, but not from Rc since it still needs to know when to drop() the value.

Alternatively, feel free to use this crate for normal use in graphs, meshes, and other recurrent data structures with lots of interconnectivity where the borrow checker simply can't help. Later, if your code works fine and you need the performance back from RefCell, just use the unchecked feature and your code will be good to go.