I wouldn't say we fall into the JSON camp at all though, but quite squarely into the XML-ish camp! We just wrap the inner text in quotes to make sure there's no confusion between the formatting of the text stored IN the document and the formatting of the document itself. HTML is hiding a lot of complexity here: https://blog.dwac.dev/posts/html-whitespace/. We're actually doing exactly what the author of that detailed investigation recommends.
You can see how it plays out when CSTML is used to store an HTML document https://github.com/bablr-lang/bablr-docs/blob/1af99211b2e31f.... Having the string wrappers makes it possible to precisely control spaces and newlines shown to the user while also having normal pretty-formatting. Compare this to a competing product SrcML which uses XML containers for parse trees and no wrapper strings. Take a look at the example document here: https://www.srcml.org/about.html. A simple example is three screens wide because they can't put in line breaks and indentation without changing the inner text!
It's particularly gratifying that you can easily interpret CSTML with a stream parser. XML cannot work this way because this particular case is ambiguous:
<Name
What does Name mean in this fragment of syntax? Is it the name of a namespace? Or the name of a node? We won't know until we look forward and see if the next character is :That's why we write `<Namespace:Name />` as `:Namespace: <Name />` - it means there's no point in the left-to-right parse at which the meaning is ambiguous. And finally CSTML has no entity lookups so there's no need to download a DTD to parse it correctly.