And BTW, thanks for supporting comments - the reason given for keeping comments out of standard Json is silly ( "they would be used for parsing directives" ).

I can see potential usefulness of this is in debug mode APIs, where somehow comments are sent as well and are rendered nicely. Especially useful in game dev jsons.

There's an older pure Python version but it's no longer maintained - the author of that recently replaced it with a Python library wrapping the C# code.

This looks to me like the perfect opportunity for a language-independent conformance suite - a set of tests defined as data files that can be shared across multiple implementations.

This would not only guarantee that the existing C# and TypeScript implementations behaved exactly the same way, but would also make it much easier to build and then maintain more implementations across other languages.

Interestingly the now-deprecated Python library does actually use a data-driven test suite in the kind of shape I'm describing: https://github.com/masaccio/compact-json/tree/main/tests/dat...

That new Python library is https://pypi.org/project/fractured-json/ but it's a wrapper around the C# library and says "You must install a valid .NET runtime" - that makes it mostly a non-starter as a dependency for other Python projects because it breaks the ability to "pip install" them without a significant extra step.

  {
    foo: "bar",
    ans: 42,
    comments: {
      ans: "Douglas Adams"
    }
  }