Important functionality cannot be modified without a full recompile, which is always annoying. Try calling, say, font-backend functions from lisp... and then try overriding them.
All of Emacs needs to be dynamic, not just some of it.
It would also be nice to allow other languages to target the Emacs VM without rewriting those languages. Something like LLVM would be a good intermediate platform; lots of compilers can generate code for it, and the various assemblies can call each other.
Most users don't care, because they just want to write a function to replace < and > with < and >... but some people writing more complex modes would appreciate cleaner internals. Why shouldn't Emacs be as fast and accurate as Yi, after all?
Well, from what I've skimmed in the emacs-devel list, there's some talk of putting guile in there, so that'd at least open up for scheme, and I guess javascript, or whatever it is that guile currently supports. This'd probably solve things like bignum support and so on too, I guess. I doubt we'd see this even in emacs25, though, but, still...
All of Emacs needs to be dynamic, not just some of it.
It would also be nice to allow other languages to target the Emacs VM without rewriting those languages. Something like LLVM would be a good intermediate platform; lots of compilers can generate code for it, and the various assemblies can call each other.
Most users don't care, because they just want to write a function to replace < and > with < and >... but some people writing more complex modes would appreciate cleaner internals. Why shouldn't Emacs be as fast and accurate as Yi, after all?