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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='color:#1F497D'>During the revision of 29500-3, we’re planning on removing some existing functionality. While that is certainly allowed, I just wanted to point out some options. Removing functionality from a standard might upset conforming implementations that produce or expect that functionality. And while WG4 members might reasonably guess that there are no such implementations, I doubt that we can actually prove that.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I see two choices:<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l1 level1 lfo3'><![if !supportLists]><span style='color:#1F497D'><span style='mso-list:Ignore'>1.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span style='color:#1F497D'>We can declare the functionality in question to be “deprecated” (sometimes referred to as “obsolescent”), which serves notice that that functionality might be removed in a future revision. We might also provide a better/alternate mechanism. The idea here is to allow implementers to plan for the changeover.<o:p></o:p></span></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l1 level1 lfo3'><![if !supportLists]><span style='color:#1F497D'><span style='mso-list:Ignore'>2.<span style='font:7.0pt "Times New Roman"'> </span></span></span><![endif]><span style='color:#1F497D'>We can remove the functionality, but we must note in the Foreword that we have done so. We would mention the rationale for such removal in our meeting minutes and prominently near the front of any Working Drafts (WDs) we make public (which would be a great reason to have broad distribution of, as well as multiple, WDs).<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>If we remove the functionality, what might happen when a future conforming consumer that does not recognize the removed feature, is presented with such a feature? A standard cannot speak to extensions implementers may provide.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>I have no stake in this decision; I simply want to make sure that whatever approach we chose has been thought through and is well documented. <o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Assuming that we chose Choice 2 above, someone will need to write the rationale, and the sooner the better. The rationale would need to be approved by WG4 before we circulate publically the first WD (post-London F2F), in which I’d include that rationale.<o:p></o:p></span></p><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='color:#1F497D'>Rex<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>