5a8dfd933a
Mir-Opt for copying enums with large discrepancies I have been meaning to make this for quite a while, based off of this [hackmd](https://hackmd.io/`@ft4bxUsFT5CEUBmRKYHr7w/rJM8BBPzD).` I'm not sure where to put this opt now that I've made it, so I'd appreciate suggestions on that! It's also one long chain of statements, not sure if there's a more friendly format to make it. r? `@tmiasko` I would `r` oli but he's on leave so he suggested I `r` tmiasko or wesleywiser.