In my previous post, I described the idea of using an edition mechanism to introduce a new auto trait. I wrote that the compiler would need to create an “unbreakable firewall” to prevent using !Leak types from the new edition with code from the old edition that assumes values of all types can be leaked. The response has been pretty optimistic that ensuring this would be possible, even though I wrote in the post myself that I “despair” over how difficult it was. I’ve received a great...
