[teleforce]

The SILE approach for macro is very limited and sane. I think that's purposely to make sure that it's simple to understand, intuitive and maintain. More complex activities or programming is delegated to Lua as mentioned in the Simon's TUGboat paper:

> SILE’s \define command provides an extremely restricted macro system for implementing simple tags, but you are deliberately forced to write anything more complex in Lua. (Maxim: Programming tasks should be done in programming languages!)