[Edu-sig] Properties use case

Chuck Allison chuck at freshsources.com
Sat Mar 25 16:39:25 CET 2006


I think they are "going on" about a very fundamental CS issue: mutable
objects are not thread-safe. If threads are not an issue, then this
has all been hot air, but it came up, IIRC, because the discussion
mentioned the "mutable vs. immutable" issue, and this always leads one
to concurrency nowadays, since so many applications have some level of
concurrency (we take it for granted in the apps we use - and more
programmers will have to face concurrency issues as time goes on; as
Herb Sutter says, "The Free Lunch is Over").

Immutable objects are inherently thread-safe, and mutable ones are
not. That's the simple truth, so, if one asks what's the diff, there
it is. I believe that summarizes the past few days of discussion to
some degree. No amount of further discussion will change the facts.

The point I tried to bring up a while back was that numeric types tend
to be *value types*, and they also are traditionally immutable, even
without considering thread-safety issues. There is room for debate
there, and I think Arthur has brought up some good points. He may have
good reason for not having his complex be a value type. I was just
saying that this was a departure from the norm, but hey, that what
norms are for :-).

Saturday, March 25, 2006, 8:21:03 AM, you wrote:

MT> Arthur (addressing you directly) does your code use any threading
MT> library at all?

MT> Did you bring up concurrency at all?

MT> If not, what do you suppose these people are going on about?

MT> mt
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-- 
Best regards,
 Chuck




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