Ha, naming is hard! You’re totally right, it used to be just the values of the last byte of a UTF-8 char (and before that it was NonMaxU8) but now represents more. I’ll update it once I’m back at my computer, thanks!
22 karma · joined May 15, 2020
> ... and another (217) signifies that it's a weird static allocation (I do not know why you'd do this)
In addition to String Rust also has str[1], which is an entirely different type. It's common to represent string literals known at compile time as `&'static str`, but they can't be used in all of the same places that a String can. For example, you can't put a &'static str into a Vec<String> unless you first heap allocate and create a String. We added the additional variant of 217 so users of CompactString could abstract over both string literals and strings created at runtime to solve cases like the example.
Fun fact, it was this fasterthanlime post that originally inspired me to play around with small strings and led to the creation of compact_str.