Hackable scheme implementation with decent C++ FFI

Question

I have tried: scheme48, chicken, gambit, clojure.

I am looking for a scheme implementation that's readable (the implementation itself), and has a decent C++ ffi, and good debugging suport (so when I get an exception, I should get popped into a recursive repl).

What suggestions do people have?

Answer 1

This page lists a few: http://linuxfinances.info/info/scheme.html. "Unlikely Scheme" might interest you as its written in C++.

Answer 2

MzScheme. It can be embedded in C/C++ programs. It can be extended with C libraries, with no special interfacing code. Checkout "Inside PLT MZScheme" for detailed documentation.