CVS difference for acs/ac-00184.txt

Differences between 1.3 and version 1.4
Log of other versions for file acs/ac-00184.txt

--- acs/ac-00184.txt	2010/02/23 07:32:51	1.3
+++ acs/ac-00184.txt	2010/10/26 05:39:20	1.4
@@ -1008,7 +1008,7 @@
 for Health Care and Indiana University School of Medicine Clement J. McDonald,
 Regenstrief Institute for Health Care and Indiana University School of Medicine
 Version: 1.6 (contains important corrections)
-Revision: $Revision: 1.3 $ Copyright C 1998-2005, Regenstrief Institute for
+Revision: $Revision: 1.4 $ Copyright C 1998-2005, Regenstrief Institute for
 Health Care.
 All rights reserved.
 http://aurora.regenstrief.org/UCUM/ucum.html#section-introduction
@@ -1241,7 +1241,10 @@
 From: Randy Brukardt
 Date: Wednesday, February 10, 2010  7:31 PM
 
-The syntax is reasonable, if you believe the assumption that all dimensions can be verified statically. I *know* that could never be true in Janus/Ada (it's an impossibility in a generic body), and Christoph had other examples where specifying the dimensi
ons statically would be hard/impossible.
+The syntax is reasonable, if you believe the assumption that all dimensions can
+be verified statically. I *know* that could never be true in Janus/Ada (it's an
+impossibility in a generic body), and Christoph had other examples where
+specifying the dimensions statically would be hard/impossible.
 
 The advantage of using discriminants should be clear: they'll work on every Ada
 compiler (with overhead), and the optimizations to remove the overhead will help
@@ -1252,7 +1255,7 @@
 Moreover, there is no need to invent new kinds of names to describe dimensions
 (the discriminant names will take care of that nicely), and really no need to
 invent anything. The trick is to hide the discriminants most of the time, and
-Christoph always has shown that can be done.
+Christoph already has shown that can be done.
 
 It seems to me that Hiflinger's statement "Dimensions as types have no place in
 Ada because they are *definable* in Ada with no extra language features." is
@@ -1509,6 +1512,67 @@
 You have to move the discrimnants of Quant to Vector. You have to bring them
 back when elements are extracted as Quants. You have to allow an efficient
 implementation of "+" in terms of Floats.
+
+****************************************************************
+
+From: Christoph Grein
+Date: Wednesday, September 8, 2010  5:13 AM
+
+This goes especially to Edmond Schonberg who is cited in
+http://www.ada-auth.org/cgi-bin/cvsweb.cgi/acs/ac-00184.txt?rev=1.3
+
+From: Edmond Schonberg
+Date: Tuesday, October 27, 2009  2:06 PM
+
+We've been discussing internally a simple scheme involving subtypes and pragmas,
+that should do most of the job and be extremely lightweight.  I notice that the
+beginning of AI95-0324 mentions that such was considered but discarded because
+it represented too much of an implementation burden.  It's true that it's all
+compiler work, but it appears to us quite doable.  Nothing will be ready to
+discuss next week, but hopefully we'll have a prototype implementation in a
+couple of months, that the community can experiment with. (Is this good enough
+to stifle your scream, at least before Valencia :-)?
+----
+Now that Valencia is past, is there anything AdaCore can present about their
+proposal for SoU?
+
+Or is Randy going to scream that we'll hear him in Europe;-)?
+
+****************************************************************
+
+From: Edmond Schonberg
+Date: Wednesday, September 8, 2010  6:24 AM
+
+1)  Ada2012 will not have any built-in features for unit consistency checking.
+    The amendment is already large enough to keep implementors busy for a
+    while!
+
+2)  At AdaCore we will add implementation-defined aspects of subtypes, along the
+    lines sketched previously, and modify the analysis of expressions,
+    assignments and the like in the compiler to take those units into account.
+    Needless to say, our work on this has lower priority than the implementation
+    of the new standard (see 1) above).
+
+****************************************************************
+
+From: Christoph Grein
+Date: Wednesday, September 8, 2010  7:40 AM
+
+> 1)  Ada2012 will not have any built-in features for unit consistency
+> checking.   The amendment is already large enough to keep implementors
+> busy for a while!
+
+This goes without saying. I didn't expect this already in 2012.
+
+> 2)  At AdaCore we will add implementation-defined aspects of subtypes,
+> along the lines sketched previously, and modify the analysis of
+> expressions, assignments and the like in the compiler to take those
+> units into account.  Needless to say, our work on this has lower
+> priority than the implementation of the new standard (see 1) above).
+
+I just wanted to know whether there is already something that AdaCore can
+present to the Ada community, i.e. a bit more than the sketches. Obviously not
+(which I understand).
 
 ****************************************************************
 

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