CVS difference for ais/ai-00274.txt

Differences between 1.1 and version 1.2
Log of other versions for file ais/ai-00274.txt

--- ais/ai-00274.txt	2001/09/21 04:07:45	1.1
+++ ais/ai-00274.txt	2001/09/22 01:18:08	1.2
@@ -487,3 +487,111 @@
 
 *************************************************************
 
+From: Robert Dewar
+Date: Thursday, September 20, 2001  10:28 PM
+
+<<Well, most compilers do have a number of "features" that meet the "forest of
+junk" criteria.>>
+
+I don't think that's true, certainly there is nothing in GNAT that has not
+met the criterion of being needed and useful by one or more of our customers,
+or is a major development that we have carefully designed.
+
+<<I think it would be best to simply say that you think that this proposal has
+insufficient value. Trying to lean on implementation concerns and the always
+useful "no effective alternative" just confuses matters. (That was my point
+above, although it may have been a bit obscure.)>>
+
+You miss my point completely. The proposal has definitely sufficient value
+IF it is really the case that at least one or more serious users of Ada
+would find it significantly useful. If one of our customers is in this
+category, and is willing to fund the development, then it would have
+sufficient value.
+
+My point is that the ARG should not be in the business of mandating new
+features merely because someone thinks something is nice to have.
+
+In the setting of a commercial vendor supplying customers, you have an
+immediate criterion of whether serious interest and need exists.
+
+That's why I suggested that a first step is a trial implementation in
+one compiler. If no one can justify this, then I see no reason to move
+further. After all many of the features we *have* added like C_Pass_By_Copy
+have exactly that history.
+
+*************************************************************
+
+From: Randy Brukardt
+Date: Friday, September 21, 2001  12:59 PM
+
+> <<Well, most compilers do have a number of "features" that
+> meet the "forest of junk" criteria.>>
+>
+> I don't think that's true, certainly there is nothing in GNAT that has not
+> met the criterion of being needed and useful by one or more of our customers,
+> or is a major development that we have carefully designed.
+
+Features added specifically for a single customer, or to provide a very
+specific need, are almost always in the "junk" category. Implementers need to
+add these things to get things done and keep their customers happy, but that
+doesn't magically turn them into well-designed language features. Every compiler
+I've looked at has plenty of them, GNAT included.
+
+> You miss my point completely. The proposal has definitely sufficient value
+> IF it is really the case that at least one or more serious users of Ada
+> would find it significantly useful. If one of our customers is in this
+> category, and is willing to fund the development, then it would have
+> sufficient value.
+>
+> My point is that the ARG should not be in the business of mandating new
+> features merely because someone thinks something is nice to have.
+
+And I've been making the same point. I just don't think it matters whether or
+not a single customer comes to ACT or Rational or whomever to add it. That is
+exactly how we get the "forest of junk" language design. My point in offering
+to add it for $195 is to prove that that criteria is too easily corrupted.
+
+In this particular case, I don't see the feature getting out of the "nice to
+have" category even if every ACT customer demands it is added tomorrow --
+precisely because ACT (and everyone else) could support it if asked without
+any help from the ARG. There are a lot a features in GNAT (presumably added
+because of customer demand) that the ARG has no interest in standardizing.
+
+*************************************************************
+
+From: Robert Dewar
+Date: Friday, September 21, 2001  1:15 PM
+
+<<Features added specifically for a single customer, or to provide a very
+specific need, are almost always in the "junk" category. Implementers need
+to add these things to get things and keep their customers happy, but that
+doesn't magically turn them into well-designed language features. Every
+compiler I've looked at has plenty of them, GNAT included.>>
+
+You are missing my point because your definition of junk is different
+from mine.
+
+My point, I will not use the word junk, is that an extra feature like the
+one proposed cannot possibly be stuffed into the language on the basis
+simply of one person saying this would be nice to have.
+
+Either lots and lots of people (a real consensus) has to agree that this
+is *so* nice-to-have that it should be put in even if there is no
+demonstrated need.
+
+Or need must be demonstrated, and for me a minimal demonstration of such
+need is that at least one vendor finds enough need to implement.
+
+
+As for features in GNAT, anyone can say anything is junk, but there are no
+features in GNAT that do not meet the above criteria. In particular, you
+may not like a particular feature in GNAT, but you can be sure that it is
+there either because there was a substantial need (and for us substantial
+need is more than just one customer being willing to buy one copy of the
+compiler, which Randy said was his (much lower)_ threshhold). For example,
+the DEC pragmas are considered by many to be junk, but there is of course
+a critical need in dealing with legacy DEC Ada code, and that is a real
+need that comes from multiple customers.
+
+*************************************************************
+

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