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Re: [JLS] new long[0][ -1 ]

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Eric Sosman <esosman@comcast-dot-net.invalid> wrote:
> On 7/10/2015 7:52 AM, Andreas Leitgeb wrote:
>> I've had a look at the JLS to find out about the more or less special
>> case of a 2-dimensional array, whose first(outer) dimension is 0, but
>> I didn't find any extra mention of that case.
>>
>>  From what I read, it would evaluate *all* the dimensions, then check
>> if any of them is negative.
>>
>> But if first dimension is 0, then the loop shown in the "equivalent as"-
>> code sample would not get its body run even once, so actually it wouldn't
>> even notice if any of the further dimensions was negative.
>>
>> What would be an accurate *purely JLS-based* prediction for
>>    new long[0][-1]
>> (not caring about actual existing JVM implementations) ?
>
>      Intriguing question, but easily answered. 15.10.2, second
> bullet, second sub-bullet:
>
> 	"Next, the values of the dimension expressions are checked.
> 	If the value of any DimExpr expression is less than zero,
> 	then a NegativeArraySizeException is thrown."

My mistake was to generalize the first example in 15.10.1-2 .

On second thought, the equivalence in the example-block is correct.
It just cannot be generalized from dimensions 3,3 to "any" (like 0,-1),
as for dims 0,-1 the compact form has to throw a NASE, while the
alternative code doesn't.

Thanks.  Knot in my brain dissolved. :-)

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[JLS] new long[0][ -1 ] Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2015-07-10 11:52 +0000
  Re: [JLS] new long[0][ -1 ] Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-07-10 08:02 -0400
    Re: [JLS] new long[0][ -1 ] Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2015-07-10 12:58 +0000
      Re: [JLS] new long[0][ -1 ] Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-07-10 09:45 -0400
        Re: [JLS] new long[0][ -1 ] Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2015-07-10 14:19 +0000
          Re: [JLS] new long[0][ -1 ] Martin Gregorie <martin@address-in-sig.invalid> - 2015-07-10 20:19 +0000
            Re: [JLS] new long[0][ -1 ] Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-07-10 16:43 -0400
              Re: [JLS] new long[0][ -1 ] Martin Gregorie <martin@address-in-sig.invalid> - 2015-07-10 22:24 +0000
                Re: [JLS] new long[0][ -1 ] Eric Sosman <esosman@comcast-dot-net.invalid> - 2015-07-11 07:33 -0400
            Re: [JLS] new long[0][ -1 ] Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2015-07-10 21:17 +0000
              Re: [JLS] new long[0][ -1 ] Martin Gregorie <martin@address-in-sig.invalid> - 2015-07-10 22:29 +0000
            Re: [JLS] new long[0][ -1 ] Arne Vajhøj <arne@vajhoej.dk> - 2015-07-27 22:10 -0400
              Re: [JLS] new long[0][ -1 ] leif.roar@dimnakorr.com - 2015-07-28 01:53 -0500
                Re: [JLS] new long[0][ -1 ] Arne Vajhøj <arne@vajhoej.dk> - 2015-07-28 19:13 -0400
                Re: [JLS] new long[0][ -1 ] leif.roar@dimnakorr.com - 2015-07-28 21:50 -0500
              Re: [JLS] new long[0][ -1 ] Martin Gregorie <martin@address-in-sig.invalid> - 2015-07-28 11:13 +0000
                Re: [JLS] new long[0][ -1 ] Arne Vajhøj <arne@vajhoej.dk> - 2015-07-31 19:41 -0400
                Re: [JLS] new long[0][ -1 ] Martin Gregorie <martin@address-in-sig.invalid> - 2015-08-01 10:23 +0000
  Re: [JLS] new long[0][ -1 ] Joerg Meier <joergmmeier@arcor.de> - 2015-07-10 17:07 +0200
    Re: [JLS] new long[0][ -1 ] Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2015-07-10 18:10 +0000

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