Macros hit the sweatspot in terms of flexibility and functionality since that can pretty much do anything that an add-in can, and they can be embedded into Revit documents.
I think that adding a function to call macros from formulas would be a great addition to Revit since it will allow complex calculated values that often get offloaded to extensions or macros to be in sync at all times with the model.
The function prototype should look something like this ``run_macro("macro_name", param1, param2, param3)``, the function shuld be called each time one of its parameters and/or some type of "context" defind by the macro changes, like I suppose all formulas do. And of course, some sort of parameter fetching will be neded on the "macro" side.
This of course brings security concerns in mind, I think that can be handled, with binary hashing or even some kind of implicit code signing if you want to be fancy, or just using the same policies that are in place for macros.
While this concept is loose idea (performance issues, security issues and general confusion for regular users are loose ties), I think it's doable and it would add a new level of flexibility to the software that I think it well deserves.
Thanks for reading, I hope you found this interesting.
