alt Hacker NewsOut of curiosity, what do you think is wrong with monomorphization-based polymorphism? The other alternatives I'm aware of are 1. type-erasure via v-table based dynamic dispatch (which Rust also has in the form of the `dyn` keyword), which has performance and memory-allocation overhead and 2. macros, which Rust also has and, if used for polymorphism, would essentially be like compile-time monomorphization, but clunkier.
Maybe I'm missing something though and there are other alternatives done differently in other languages?
The correct choice IMHO is type-erasure. It does not necessarily have overhead, because optimizers can specialize or devirtualize. Of course, this my depend on how you implement your language, but in C this works nicely. The problem with monomorphization is that it leads to exponential expansion, which later passes of the compiler can not unify again (at least this is much harder than not expanding in the first place). It should also fundamentally limit what you can do, because expansion has to stop at some point, but I haven't thought about this too much.
I also think that where you want monomophization, macro seem fine. I do not think this necessarily has to be clunky, but this is just a guess.