On Thu, Sep 3, 2009 at 9:57 AM, Devon McCormick<[email protected]> wrote:
> when you talk about going beyond the boundaries in both directions, would
> you be thinking of negative indexes for before the beginning of the array?
> If so, this would conflict with existing usage.
I do not think this is the case, because
[1] The adverb would be redefining the indexing operation, and
[2] The adverb could be thought of as providing sufficient fill after
the array to make this result consistent.
In other words: { !.:. and { are two different verbs and should
not be expected to be the same verb. But, also, if you have
a 5 by 5 array of integers, and add five rows and five columns
of padding, any valid negative index into the original array would
necessarily retrieve a zero when applied to the modified array.
> It sounds like you're talking potentially about something like a sparse
> array.
Well... in the sense that they both represent arrays, and they
both have fill elements as a part of their definition, yes.
But they would not have much else in common.
--
Raul
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