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<DIV>There have been a lot of messages flying back and forth on this idea of adding some sort of tagged ref. I'm afraid I've gotten lost on what exactly is being proposed.</DIV>
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<DIV>Can someone please succinctly state the proposal again along with the reasoning behind why it should be done--what does this change enable us to do that we couldn't do before? Based on the messages, I'm not sure that Mika, Tony, Rodney, et al are all saying the same thing.</DIV>
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<DIV>Also, not sure I clued into the significance of the LSB value.</DIV>
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<DIV>Regards,</DIV>
<DIV>Randy<BR><BR>>>> <hendrik@topoi.pooq.com> 4/17/2009 6:02 PM >>><BR>On Fri, Apr 17, 2009 at 12:54:13PM +1000, Tony Hosking wrote:<BR>> <BR>> On 15 Apr 2009, at 02:56, Mika Nystrom wrote:<BR>> <BR>> ><BR>> >I agree with what Hendrik says, but what about TYPECASE, ISTYPE,<BR>> >NARROW? Those are necessary to make it possible to pass "pointers"<BR>> >with the low-order bit set outside of unsafe code.<BR>> ><BR>> >My feeling is that if Tony can make the necessary changes, it could<BR> should<BR>> >be done immediately, and the language issues can be pushed to the<BR>> >future. But admittedly I'm biased because of the application I'm<BR>> >working on.<BR>> <BR>> I can take care of this next week.<BR><BR>I'm in favour of trying it out before freezing the feature. That <BR>means going ahead now with an implementation, and reconsidering it <BR>in a few months. Perhaps marking it experimental with an appropriate <BR>warning message. A few months is little enough time to use it that it <BR>won't be traumatic if code that uses the new features has to be <BR>partially rewritten.<BR><BR>-- hendrik<BR><BR></DIV></BODY></HTML>