You are certainly right in that observation. But there is slightly more to it. The "generic" concept from Java and C++ is more akin to the functors of the ML fa

You are certainly right in that observation. But there is slightly more to it. The "generic" concept from Java and C++ is more akin to the functors of the ML family. In that view, the question is not how to efficiently compile functions that are polymorphic (SML/NJ does that quite well, I think). The real question is, what are your compilation units. If you optin to the OCaml view, then Modules (and Functors) have to be compiled separately. Everything else follows. Java looks at this in a similar fashion, btw. If you optin to the C++ view, than only monomorphic code has ever to be compiled. In that scenario a template has no meaning on its own, except as an abstraction over code to be generated when needed. In principle, SML/NJ shows how both views can be reconciled. One can easily envision separate compilation up to the point of specialization which is then done in a separate phase just before linking. I think no one does it that way, though, except maybe Swift.