Having in mind Entity System (ES), that is a great step towards pluggable ends (like a graphics engine, etc), I wonder if someone managed to create code in an algorithm only way, that would easily let us generate java or c# or c++, or even lua code? (or any other language)
The core of programs are basically algorithm logic and data. We just need tools to convert such core logic (that must not depend on external libraries). Such special core code, that is intended to survive "forever", would have to be simple enough to depend only on itself (so anything extra or feature dependent, would have to be supplied by external libs). Therefore a set of tools to generate any specific target language code would be required.
As a "this question validity breaker", any language converter (from c# to java or c++ etc) (and within it's limitations) could be enough, not requiring the effort on using some special language that could be converted to everything else easily (within limitations).
As a reference, I am programming in java, on linux. And I want to be more sure that I will create something that may one day be ported to use next gen graphics available on any platform, with the less conversion effort possible.