🚀 go-pugleaf

In article <9235622.25712@mulga.cs.mu.OZ.AU> fjh@munta.cs.mu.OZ.AU (Fergus James HENDERSON) writes:
>maxtal@extro.ucc.su.OZ.AU (John MAX Skaller) writes:
>
>>pat@frumious.uucp (Patrick Smith) writes:
>>>   p == q   =>   ptrcmp(p,q) == 0
>>
>>	I'm NOT agreeing with this at present. I reject any relationship
>>between p ? q and ptrcmp. On some machines any such relationship
>>might make ptrcmp unimplementable, and thus defeat the proposal completely.
>
>I remain unconvinced that such a relationship is unimplementable on
>some machines.

	On the 486 it is not in general possible to implement
the comparison p==q for arbitrary logical addresses. If p and q
are aliases only the operating system kernel could implement 
the comparison, and if the OS happened not to support this,
p==q could not be implemented.

>
>>It is only Jims suggestion that ptrcmp might always return 0 that
>>makes it possible to make its existence mandatory.
>
>A ptrcmp that always returned 0 would be useless, IMHO.
>

	Not at all. My sort will still order the pointers
into the total order, which in this case is anything.

	This is entirely different from the current situation
where a sort based on the existing implementation defined <
on pointers might not terminate.

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        JOHN (MAX) SKALLER,         maxtal@extro.ucc.su.oz.au
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