CVS difference for ais/ai-00239.txt

Differences between 1.1 and version 1.2
Log of other versions for file ais/ai-00239.txt

--- ais/ai-00239.txt	2000/07/21 00:23:33	1.1
+++ ais/ai-00239.txt	2000/08/01 05:39:34	1.2
@@ -1,5 +1,5 @@
 !standard 3.9.2  (18)                                  00-07-20  AI95-00239/01
-!class binding intrepretation 00-07-20
+!class binding interpretation 00-07-20
 !status work item 00-07-20
 !status received 00-07-20
 !qualifier Error
@@ -16,20 +16,9 @@
 Consider the following example:
-package Pkg0 is
-    type T0 is tagged null record;
-    function Fa return T0;
-    procedure Pa (P : in T0 := Pkg0.Fa);
-end Pkg0;
-with Pkg0;
 package Pkg1 is
-    type T1 is new Pkg0.T0 with null record;
+    type T1 is tagged null record;
     function Fa return T1;
@@ -37,7 +26,7 @@
 end Pkg1;
-with Pkg0, Pkg1;
+with Pkg1;
 package Pkg2 is
     type T2 is new Pkg1.T1 with null record;
@@ -131,7 +120,7 @@
 Additionally, the literal reading of the standard means that a call can have
 a parameter with the *wrong* tag. Consider the following similar example:
-with Pkg0, Pkg1;
+with Pkg1;
 package Pkg3 is
     type T3 is new Pkg1.T1 with record
@@ -491,6 +480,39 @@
 end Frn622;
+From: Jean-Pierre Rosen
+Sent: Friday, July 21, 2000 2:36 AM
+My first reaction is: can't we simply state that the call is illegal, precisely because the types do not match?
+After all, using a default value is equivalent (safe for visibility oddities) to writing the default value explicitely, and as you
+From: Gary Dismukes [dismukes@GNAT.COM]
+Sent: Friday, July 21, 2000 1:13 PM
+Not realistically.  Such calls were also allowed in Ada 83 for untagged
+derived types.  We can't consider creating that kind of incompatibility.
+We know what semantics we want for the call, it's just a matter of
+coming up with the proper RM wording to handle it :-)
+From: Randy Brukardt
+Sent: Friday, July 21, 2000 1:28 PM
+Well, that would of course be incompatible with untagged types. It would be
+necessary to repeal part of 3.4(22) in order to implement that rule. It also
+would make the rule of 3.9.2(11) unnecessary (so in that case, it should be
+repealed as well, as it is very annoying).
+So I don't think that would be an improvement over rewriting 3.9.2(18).

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