[plt-scheme] Are web cells space-safe?

From: Jay McCarthy (jay.mccarthy at gmail.com)
Date: Sat Mar 24 10:35:22 EDT 2007

Hey Alessandro,

On 3/23/07, Alessandro Colomba <acolomba at gmail.com> wrote:
> I'm afraid I was not very precise in my original formulation. I meant
> to confirm that, as long as any one continuation is not expired, the
> chain from the frame it wraps to the root frame is uninterrupted, even
> if the continuations wrapping the individual frames in the chain have
> been garbage collected.
> The rest of your message seems to imply that is indeed the case.

Correct. I have thought about doing a collapsing of all the previous
frames into a single (or fewer frames) and have a way to do it that
would be safe, but I haven't found it worth implementing based on Web
cells' performance in Continue, Resume, etc.

> In general, is there any particular reason web cells are not yet a
> documented feature in PLT? I understand that they work very well for
> CONTINUE, and, from my perspective, they fill a need often
> communicated by SISCweb users.

The particular reason that they are not documented is that I am a lazy
bottom. The documentation is in such horrendous shape that I have
shied from even adding pieces of good information. There's no excuse
and it should be resolved.

> Are there any gotchas I should keep in mind?

Not so much. Perhaps when you have an implementation I can send my
test cases (which eventually will probably be examples in the manual.)


Jay McCarthy <jay.mccarthy at gmail.com>

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