> Behalf Of Mark D. Niemiec
> Jose Mario Quintana <[EMAIL PROTECTED]> wrote:
> > "5!:5 y Linear. The linear representation is a string which, when
> > interpreted, produces the named object."
> >
[...]
>
> One of the idiosyncracies of empty arrays is that they are
> considered equal, even if they have different data types.
> This is rarely important, but the underlying data type can
> reveal itself when fill elements are being used (as with {. or {:)
> and certainly with 3!:0
>
[...]
> A problem with 5!:5 and 5!:6 is that they produce representations that are
> equal to the original, but not necessarily IDENTICAL in all
> aspects. For example, they do not preserve type:
>
> type f0=:-~1.5 NB. real clone of 0
> 8
> f0
> 0
> type "[EMAIL PROTECTED]'f0' NB. This forgets the 'realness' of the zero
> 1
> f0+!20x NB. real 0 trumps extended precision
> 2.4329e18
> ("[EMAIL PROTECTED]'f0')+!20x NB. freeze-dried and reconstituted 0 does not
> 2432902008176640000
>
> (and, in the cited example, lr does not preserve the type of the empty
> list either).
> Behalf Of Roger Hui
> It comes down to whether there is one empty vector
> or more than one empty vector. (*)
[...]
>
> I will probably change 5!:5 to preserve the
That seems to make more sense than the alternative of clarifying that "when
interpreted, produces the named object" but it might not always be
'identically' the same object.
By the way, a particular application failed to run because a J6 empty vector
turned out not to be 'identical' to the corresponding J5 empty vector and it
was difficult to see, via their linear representation, that they were
actually different in some sense.
> distinction between <i.0 and <'' without answering
> (*) one way or the other.
>
>
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