Re: vm branch now uses vm repl by default

["Neil Jerram" <neiljerram@googlemail.com>]

2008/9/9 Andy Wingo <wingo@pobox.com>:
>
>    Sources:
>
>       8    #(1 11 #f)
>
> Some instructions are annotated with source information.

I guess source information is of interest for debugging, and I think
you've observed previously elsewhere that the VM doesn't yet have much
debugging support - by which I presume you mean something like the
traps that the evaluator has.

So I was just wondering if we actually _need_ any debugging support in
the VM.  If we can assume that the VM will always behave equivalently
to the evaluator (except faster), then whenever a piece of code needs
step-by-step debugging, the developer can drop back to using the
evaluator in order to do that.

Does that make sense?

(Then another question is whether we can assume that the VM behaves
equivalently to the evaluator.  I wonder if there is some test
methodology for partly proving this, by automatically running the
evaluator in parallel with the VM, at least for code that doesn't have
side effects?

I'm sorry, this email has ended up a bit vague....)

      Neil