From ploedere@grimm.informatik.uni-stuttgart.de Thu Nov 28 17:42:53 1996 Return-Path: Received: from inmet.camb.inmet.com by camb.inmet.com (SMI-8.6/SMI-SVR4) id RAA12240; Thu, 28 Nov 1996 17:42:50 -0500 Received: from sw-eng.falls-church.va.us (ns1.sw-eng.falls-church.va.us) by inmet.camb.inmet.com (4.1/SMI-4.1) id AA25684; Thu, 28 Nov 96 17:43:12 EST Received: from ifi.informatik.uni-stuttgart.de by sw-eng.falls-church.va.us (8.7.1/) id WAA08950; Thu, 28 Nov 1996 22:40:20 GMT Date: Thu, 28 Nov 1996 23:41:56 +0100 (MET) Message-Id: <199611282241.XAA15920@hesse.informatik.uni-stuttgart.de> Received: by hesse.informatik.uni-stuttgart.de; Thu, 28 Nov 1996 23:41:56 +0100 (MET) From: Erhard Ploedereder To: ada-comment@sw-eng.falls-church.va.us Subject: Re: Convention of an overriding dispatching operation content-length: 1395 !topic Convention of an overriding dispatching operation !reference RM95-3.9.2(10) !reference RM95-6.3.1(3) !reference 95-5394.a Tucker Taft 95-11-21 !reference AI95-00117 !reference 96-5759.a Robert A Duff 96-11-18 !from Erhard Ploedereder <> !discussion In 96-5759.a, Bob argues that the rules proposed in the AI and some improvements suggested at the recent meeting all share the problem that they violate the privacy principles of Ada. This is true. However, the current ARM semantics do so in the very same way by requiring the user to specify a pragma on inherited primitive operations, while he has no business knowing about the Convention Pragma applied privately to the original operation. In fact, the situation is worse than under the AI: The RM requires explicit action to react to something supposedly unknown. Under the AI, at least no such explicit action is required, albeit that 'Access ramifications may exist (as they do for the RM). Bob argues further: > Another issue: 6.3.1 defines the default convention for subprograms, and > for access-to-subprogram types. Should it not also define the default > convention for everything else (e.g. record types)? Very good point and it does need to be addressed. (Wouldn't this be a natural fall-out of implicit inheritance of Convention from types, as I understood the cited alternative solution suggested at the meeting ?)