Re: syntax-local-binding

[Andy Wingo <wingo@pobox.com>]

Hello Mark :)

Thanks again for your deep thoughts.  This conversation is a bit
stressful for the both of us, but we wouldn't be having it if we didn't
both care about Guile.

In the spirit of diffusing tension here, feel free to imagine all of my
words as coming from Mr. Collins for the duration of this thread ;-)

On Tue 24 Jan 2012 14:25, Mark H Weaver <mhw@netris.org> writes:

> Andy Wingo <wingo@pobox.com> writes:
>
>> None of the interfaces that I proposed leak internal psyntax
>> representations.
>
> `syntax-local-binding' leaks the internal representations used for
> bindings.

You mean, whether something is a lexical, or a macro, or a global, or
whatever; OK.  I think that "leak" is the wrong word here: leaks are
inadvertent, whereas providing this information is what this function
was designed to do; and furthermore it's not a detail of psyntax (cf
Racket which does not use psyntax).

Let me offer another example of its utility: writing a macro stepper.
Again, for an example I'll have to link to the PLT folks' great work:

  http://docs.racket-lang.org/macro-debugger/index.html

With syntax-local-binding, syntax-locally-bound-identifiers, and a
couple hooks that get fired when a macro is expanded and reconstructed,
you could implement a macro stepper for Guile.

And, once we provide those hooks, you can implement this in a module.

Pretty sweet, if you ask me!

Perhaps, though, at this point we're just going to have to agree to
disagree; surely we have plumbed the depths sufficiently.  It's not
satisfying, but I think we both made a great effort to communicate and
convince -- and in some cases, to work on each other's code.  We really
need to move on here.  I will re-post my patches taking into account
your comments regarding the form of the environments.

Regards,

Andy
-- 
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