call/cc

Sadly, quine generation is lost. The problem is that it's now unsound to assume tight connection between input and output (I am guessing, almost everywhere, but have a test case for lists in particular). Any ideas how to work-around that?

Otherwise, another complication is that we don't have the full power of call/cc because we don't have a top-level, which prevents us from expressing many of the idioms we normally see.