2653
2654
2655

Now we're guarding incompletely eval'd args too well.

  x2 <- (eval 'x)
  => (object incomplete_eval ((object function {sig, body, }) x))

I'd like it to be (object incomplete_eval x).
2656

Still struggling to come up with a failing test.
2657 - a draft protocol for speculative evaluation
2658
2659 - speculative evaluation now working

Anticipated idiom for compiling code:
  aif (incomplete? (eval body.f))
    (<- optimized_body.f it)
2660 - better idiom: (optimized_body.f <- (speculatively_eval body.f))
2661