[pizza]

There should be debuggers for interpreted dynamic languages that can be scripted with strict type systems. Possibly like eg prolog; like if I have Python code that has a Person class defined in it, I could just check for invariant violations with the debugger, eg check self.parent != self.child and whatnot. Then if I come up with a nice check while debugging I should be able to save that as a unit test for the project straight from the debugger, etc.

[pizza]

Also edit to add:

we have pretty magnificent tools for the mapping to a shared semantics of syntax-

    tree-sitter :: any syntax -> 1 semantics

- we have tree-sitter, lsp, etc; any language can be added with an easy description.

But we don't have great tools for mapping (1 semantics -> any syntax) - in some sense, the inverse of tree-sitter:

    inverse-tree-sitter :: 1 semantics -> any syntax

If we did, we could have a universal any language meta-debugger library.

The key impact of this is that anybody from some individual language could add a plugin, which could apply to every supported language that uses the subset of features that apply to that plugin.

Think about the network effects of a language which has a large universe of plugins - now think about the even greater network effects if it could be a union of supported languages - that's strictly at least as good, if not vastly more network-effectful. So I think the benefit to people would increase rapidly if people contributed to it across many different languages, so it could be a good collaborative tool.

I bring this up under this discussion because the debugger would be the exact best place to apply something like the inverse of tree-sitter

pretend I'm not ignoring this would likely lead to a strangely organized library with lots of potential spots of inter-language interface annoyances, so it would not probably be strictly better... :)