Author seems to use misfeatures of a particular implementation to tar all implementations with. The round-tripping issue is not a statement about YAML as a markup language, much in the way a rendering bug in Firefox is not a statement about the web.

Stepping back a bit, YAML is good enough, and this problem has been incrementally bikeshedded since at least the 1970s, it is time to move on. Human-convenient interfaces (like YAML, bash, perl) are fundamentally messy because we are messy. They're prone to opinion and style, as if replacing some part or other will make the high level problem (that's us) go away. Fretting over perfection in UI is an utterly pointless waste of time.

I don't know what NestedText is and find it very difficulty to care, there are far more important problems in life to be concerned with than yet another incremental retake on serialization. I find it hard to consider contributions like this to be helpful or represent progress in any way.

> Stepping back a bit, YAML is good enough, and this problem has been incrementally bikeshedded since at least the 1970s, it is time to move on

Nah, in the 1970s we had Lisp S-expressions that completely solved the problem, and everything since then has been regressions on S-expressions due to parenthesis phobia.

After hearing that thing about the country code for Norway, I became convinced that YAML has to just die. Become an ex-markup language. Pine for the fjords. Be a syntax that wouldn't VOOM if you put 4 million volts through it. Join the choir invisible, etc.

This is good: https://noyaml.com/

Erik Naggum had a notoriously NSFW rant about XML (over the top even for him) that I better not link to here, but lots of it applies to YAML as well.

S-expressions don't solve the problem at all, you just get to fractally bikeshed all over again about what semantics they have and what transformations are or aren't equivalent. Does whitespace roundtrip through S-expressions? Who knows. Are numbers in S-expressions rounded to double precision on read/write? Umm, maybe. How do I escape a ) in one of my values? Hoo boy, pick any escape character you like and there's an implementation that does it.