@samth I meant to ask a similar question, perhaps units are the answer? SML has a module system, and it has parameterized modules (called “functors” in the language)—they receive a module or modules and produce a new module. Does racket have something similar?

Units are that thing

@samth After reading the doc, it seems that units are parametrized at runtime, right? So I guess that comes with a runtime penalty since the compiler can’t know what the parameter values will be?

units can be parameterized at runtime, so an inner loop indirected through units will have some runtime cost. I don’t think it’s that much in any case I’ve encountered, though.