Hmmm. I guess I could also ask "What does readall do?" and go on speculating to myself, but the stuff above is what I really want to know. Once I've defined something (macro, function), what does it look like in Arc? Is its structure, either before or after macroexpansion, available to play cute little tricks with?
I'll stop asking questions now. I feel I'm reaching the limits even of assumption and might start getting silly. (For instance: "Could I write a function that let me select nodes within a loaded function using CSS Selector syntax?", but that's just silly so I won't ask it).
Sorry for asking obtuse questions obtusely. Let me try this way:
How much would codetree need to change to accept a function or macro as input instead of a file, and produce output that is similarly meaningful? (Not at all, a little bit, a lot).
Sorry again for poor question quality, and to harp on what increasingly appears to be an unimportant point.
I assume by taking a fn as input you mean taking a fn whose return values would become the input. That would not be hard, but the clean way to do it would be to modify read so that it could take a fn as an argument.
