1. Yea the goal would be some kind of validation at parsing time. I'm not super familiar with TOML parsing, but there must be error cases in the implementations, so it seems like using `\` on UNIX systems, for example could return an error. The only hard part about this I see is distinguishing paths from strings syntactically without making TOML overly complex.

2. So basically, the majority of people don't want to type version numbers (I see where they are coming from, but respectfully disagree). I'm not sure if there exists a solution in that case. As for my comment, I was really talking about both kinds of versioning. Mainly that, if my data is version 2.3.1, I'd expect that to also lock the version of TOML, requiring a new version of my data for bumps to the underlying data structure. Again syntax is the hard part, as I'm having trouble imagining a way to actually do this. Furthermore I've seen data formats in the past that let you version "parts" of a format, I personally like this, but don't think it's a good fit for TOML.