orchid/SWAP.md

Must figure out how preprocessor can both be a System and referenced in the interpreter

Must actually write macro system as recorded in note

At this point swappable preprocessors aren't a target because interaction with module system sounds complicated

Check if any of this needs interpreter, if so, start with that

alternate extension mechanism

The Macro extension needs to be in the same compilation unit as the interpreter because the interpreter needs to proactively access its datastructures (in particular, it needs to generate MacTree from TokTree)

Ideally, it should reuse orchid-extension for message routing and decoding.

orchid-host accepts extensions as impl ExtensionPort