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[REBOL] R: Re: Rebol Crash Was Mutability and sameness - a puzzle

From: rotenca:telvia:it at: 19-Jul-2001 2:52

"Ladislav Mecir" <[lmecir--mbox--vol--cz]>
> For the MUT-EQUAL? function to work more satisfactorily we need a better > LENGTH? function. Here is my trial: > > indexz?: function [ > series [series!] > ] [orig-tail result] [ > orig-tail: tail :series > while [ > error? try [result: (index? :series) - 1] > ] [ > if empty? head :series [ > append :series #"1" > ] > append :series head :series > ] > clear :orig-tail > result > ]
Why not: indexz2?: func [series [series!] /local result][ if error? try [result: -1 + index? :series ] [ result: index? tail head :series ] result ] I think that "tail series" should be always the same: a relative position not an absolute one. Tail should be always the end. When you remove an item, tail should dinamically change. So a and b in this case should be(come) the same. I think that could be util a function to discern if data adressed by series share the same memory. In this case a and b share memory (you can do "tail head b" to prove). Same? like mut-equal? makes a difference between series at different position. About discernibility i don't understand a thing: if you think of it as "total" indiscernibility (like Leibniz), so a <> b because "root" are different, or data indiscernibility, so a word and a path or two different word can be the same only because they address the same memory data. I think that if two item of Rebol were totally indiscernibles, we could not ask if they are the same, because we could not discern them. I liked your articles very much.
> Regards > Ladislav
ciao romano