pets at cs.mu.OZ.AU
Mon Dec 7 14:12:06 AEDT 1998
Is there a difference between mostly unique input and unique input?
As far as I can see, a promise not to copy a pointer to any part of a
term should not depend on how many solutions that predicate has, so I
would argue there isn't a difference. The problem with multiple
solutions comes up when one wants to destructively modify something,
which requires both deadness and uniqueness.
This then raises the question: is there a useful difference between
the unique and mostly unique insts? I'm not as sure about this, but I
don't see this difference either. If there isn't a meaningful
difference, I think it would be a good thing to remove that
distinction from the language.
Peter Schachte | PL/1, "the fatal disease", belongs more to
mailto:pets at cs.mu.OZ.AU | the problem set than to the solution set.
http://www.cs.mu.oz.au/~pets/ | -- E. W. Dijkstra
PGP: finger pets at 184.108.40.206 |
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