I and some others are working on a rough approximation to linear types here: https://github.com/Manishearth/humpty_dumpty https://github.com/Manishearth/humpty_

I and some others are working on a rough approximation to linear types here: https://github.com/Manishearth/humpty_dumpty https://github.com/Manishearth/humpty_dumpty A perfect implementation can be added to the language, but getting it to work perfectly with backcompat is hard so it might be made in 2.0.