Re: Garbage collection (was a spinoff of a spinoff of a GA

["W. Wesley Groleau (Wes)" <wwgrol@PSESERV3.FW.HAC.COM>]

Robert Dewar says:

:> Wes says
:>
:> "And with composites, the provider of the data type has the complete freedom
:> of choice to extend a controlled type with GC, extend a controlled type
:> without GC, or not use a controlled type.
:>
:> So, compared to the above, how big is the payoff of having GC imposed on
:> you by the implementation?"
:>
:> I don't think it is quite that simple. There is nothing to prevent a
:> compiler having....

You are refuting a claim I didn't make.  My QUERY was, "Since Ada now
lets us customize garbage collection (or lack of) to each ADT, how many
_Ada_ designers would be willing to pay extra for a reliable transparent
global GC?"  I doubt that any would be willing to pay for one that is
unreliable or non-transparent.

Part of the Ada philosophy (at least for me) is that if something is a
requirement, I want to see it somewhere in code.  If it isn't a requirement,
I don't want it cluttering the code AND I don't want it interfering with
requirements (including cost and schedule requirements).

"see it somewhere in code" can be satisfied by adequate guarantees from
a vendor or from testing that the requirement is met.  Can obtaining those
guarantees be easier than properly engineering one's ADTs?  Is this another
hazard comparable to "reuse without review"?  (Please don't resurrect
Ariane 5 :-)

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W. Wesley Groleau (Wes)                                Office: 219-429-4923
Hughes Defense Communications (MS 10-40)                 Home: 219-471-7206
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