[e-lang] Paper Comments
danfuzz at milk.com
Thu Jun 30 21:19:56 EDT 2005
Here are my comments based on a single reading of the draft posted as of
about 4pm today. As Ping(? I think) said, my terseness is meant merely
as an expedience. Overall, I think the paper is excellent; most of my
comments are minor nitpicks. Also, apologies if any (all?) of this is
stale; I wish I had time to keep up with it all!
> The Sequential StatusHolder introduces the statusHolder, and examines
> hazards in a sequential environment.
I wouldn't use a comma there, since the thing after the comma isn't a
full sentence, nor is it part of a list of 3 or more clauses. You do the
same thing in the rest of the list of sections as well.
> Hayek’s explanation of how property rights protects humans plans from
Some syntactic issues there.
Fig.1: I don't get what the double-headed arrow in the middle of the
figure is supposed to represent.
Fig.2: I just want to cast my vote in favor of the line drawing over the
If the suggested replacement "A vat runs an event loop..." is taken,
then the definition of "vat" two paragraphs hence should be moved
earlier or integrated into that replacement.
> (**unclear**) AM has given X and F access to the statusGetter.
"statusGetter" isn't in the code font (a second time in the paragraph as
> Ask Hopwood what he means by “E doesn’t rely on other vats to
> implement the E
I know I'm not Hopwood, but I bet the idea is that an E vat doesn't rely
on anything it communicates with being a well-behaved E vat. It *could*
be, but if not, there's nothing that the miscreant alleged-vat could do
to corrupt the well-behaved vat it is communicating with. It's another
riff on "Don't let the protocol be capable of expressing lies."
> Promise chaining provides a way to allow some plans...
How about "Promise chaining allows some plans..." ?
> There is no one best strategy...
How about "There is no single best strategy..." or "...unique..." to
avoid a confusing misparse of "no one" (which caused me to reread it a
couple times before realizing my mistake)?
> If it does reconnect, it knows it may have missed updates in the
> meantime, so
> it should first send a new getStatus query to refresh its own state
> before >resubscribing.
That's fine for a simple system like the statusHolder, but I think it's
worth at least addressing how a more complicated system would work,
where effectively-lost update messages between a non-atomic sequence of
getStatus() and addListener() might lead the client to an incomplete
view of the object.
FWIW, I regularly run into the equivalent of this problem, and usually
solve it by having addListener(), in addition to adding the designated
listener, also send the object's current full state to the listener in a
series of messages. (I know that's not necessarily the ideal solution.)
> Thus its semantics are a bit like having thousands and thousands of
> all hooked together
Is that a (minor) misquote? "computers"?
The title of the paper is "Concurrency Among Strangers: Programming in E
as Plan Coordination" but the Discussions and Conclusions section
doesn't make an explicit tie-in either to "strangers" or "plan
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