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Re: Bug involving VECTOR-PUSH-EXTEND
Beg to differ (though only a little). Apparently, KCL uses the
current size of the vector as the default extension (must be in the
report some place). Of course, extending a vector of size zero by
zero elements still causes trouble. CLtL only says that, in the
absence of a third argument "it defaults to a ``reasonable''
implementation-dependent value". Whether using the current size is
``reasonable'' can be left to discussion. See:
KCl (Kyoto Common Lisp) June 3, 1987
>(setq v (make-array 0 :fill-pointer 0 :adjustable t))
>(vector-push-extend 1 v)
Error: The index, 0, too large.
Error signalled by VECTOR-PUSH-EXTEND.
Broken at VECTOR-PUSH-EXTEND. Type :H for Help.
>(vector-push-extend 1 v 10)
I have had this problem before. The way I handle it is through the
(make-array <random, non-0 initial size> :fill-pointer 0 :adjustable t)
and the problem will go away. (Allocating 1 element for an
adjustable array is not so bad.) Alternatively, get used to
supplying a third argument to vector-push-extend (a practice that
gives you better control anyway). Hope this helps.
Cesar Augusto Quiroz Gonzalez
Department of Computer Science ...allegra!rochester!quiroz
University of Rochester or
Rochester, NY 14627 email@example.com