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Postings from September 2000
On 20 Sep 2000 04:06:02 -0000, Perl6 RFC Librarian wrote:
>Ilya Zakharevich brought up the issue of a potential problem with
>objects which use blessed list references as their internal structure,
>and their use as indices. Given a Bignum class, which stores its
>(external) value internally as a list of integers, doing something
>like:
>
>my $bignum = Bignum->new(23) # stored internally as [ 2, 3 ]
>print $array[$bignum]; # should it print $array[23] or $array[[2,3]]?
>
>can be ambiguous. I'm not so sure. I think that $bignum is not
>legal, under Perl5, to be an array index, and that if it is going to
>be use so, it would need to be $array[$bugnum->value] anyway.
Hmm... the problem is, I think, that array references and ordinary
scalars are both scalars.
What would be the difference between
$a[2]
and
$a[[2]]
anyway? Aren't these just the same?
If so, why not grab back into the old box, and get the syntax for
"multidimensional hashes" in perl4?
single dimension: $hash{$item}
2 dimensions: $hash{$item1, $item2}
Note that because of the '$' prefix, this cannot be confused with a
narray slice:
hash slice, not multidimensionanl hash: @hash {$item1, îtem2}
So, the similar syntax for ordinary arrays would then be:
$array[2, 3]
not $array[[2, 2]]
Please feel free to corrct me if I'm wrong.
--
Bart.