alt Hacker News> At some point, you've got to overcome the fear of getting it wrong and ship something.
Also Editions mean we can go back and fix things "for the future" in some cases if that's worth the price. For example I believe it's worth the price for the built-in ranges to become IntoIterator, indeed I hoped that could happen in the 2024 edition. It was, I think we'd both agree, worth it to fix arrays in 2021.
This is one of the less celebrated but more important wins of Rust IMO because it not only unlocked relatively minor direct benefits it licensed Rust's programmers to demand improvements, knowing that small things were possible they wanted more.
Yeah, the edition thing is cool, but there's also a cost to it, which is that over time you accumulate more and more support code in the compiler for really ancient editions.
I don't have a super good understanding of how it actually works in rustc. In C++ typically they would use name mangling tricks to try to keep new and old standard library symbols from clashing if they decided to break compatibility. Probably with rustc they are happier to leave it unspecified. I have a hard time building a mental model of what kinds of things would be totally impractical to change with an edition.