[jmcphers]

It is true. Some things you can't build in extensions for VS Code are:

- core services (Positron's core language system is an API, and R and Python are extensions) - native panes (you can contribute webview panes but they're slow!) - toolbars for other panels, or global toolbars - modal dialogs or any UI other than notifications and quick-pick lists - custom layouts

At a higher level, Positron is a platform that contains data science tools for _other_ extensions to use, and doesn't make sense as an extension itself. The R and Python extensions are the first two we built, but the platform is extensible to other languages.

[Lramseyer]

Another one is custom CSS (though it doesn't look like positron does that.) You can change styling properties like spacing and weighting as well.

I have a love/hate relationship with the VScode webview panels, but the message handler is not my favorite implementation in the world. I would love a way to send binary data, and get semantic token colors.

The only issue is that when you have a custom build of VScode, you have to manage a fork of VScode, and potentially pull in updates as VScode updates. How do you manage that?

[gclawes]

What's different between Postiron's core language system and language systems like LSP and DAP?

[jmcphers]

It's a higher-level construct. LSP and DAP are both used by Positron! But they're a pretty small subset of everything you actually want to do with a language. For example:

- discover all the interpreters on the system for the language (e.g. 'find me all the Pythons')

- start an interpreter session for the language

- run a fragment of code in the language and return the result

- get all the variables in the current interpreter session for the language

- view data defined in a particular variable

etc.

We generally try not to invent new protocols; in addition to LSP and DAP, we use Jupyter messages and kernels for most of the above. Positron only has custom protocols/APIs for the bits that are outside the purview of existing protocols.