Comment by catlifeonmars

> Actually my own problem with XML was annoyance that back when I had the thought of doing a complex config format in XML, the idea of modifying it programmatically while retaining comments turned out to be absolutely non-trivial. In comparison with the mess one can make with YAML that's just a trivial thing

Only relatively few parsing libraries preserve the token stream metadata in the AST, most don’t even expose the AST. For the former, I can understand why, it’s a cross-cutting concern and adds complexity to the AST parse, but is almost always worth it.