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Re: Variable attributes (was Re: RFC 355 (v1) Leave $[ alone.)

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Jeremy Howard
October 1, 2000 14:39
Re: Variable attributes (was Re: RFC 355 (v1) Leave $[ alone.)
Message ID:
Dan Sugalski wrote:
> At 11:33 AM 10/1/00 -0700, Peter Scott wrote:
> >But, setting aside my visceral reaction to changing array bases, you have
> >precisely the same problem here that has scuppered my intent to file an
> >RFC for hashes with fixed keys; how do you apply the attribute to
> >anonymous, let alone autovivified, arrays?  If I say
> >
> >         my @a :base(1);
> >
> >then what of $a[1][1]?  How to specify that the second level array also
> >has a base of 1?  Without it looking really ugly?
> Well, it'd be reasonable for autovivified arrays and hashes to inherit the
> properties of their parent, so if you had:
>    my int @foo;
> and accessed $foo[1][2], that new autovivified array would be of type int.
That's exactly what we've proposed for compact multidimensional arrays, for
instance (from RFC 203):

A list (of lists...) that contains elements of the same type can be
converted to an array by specifying its type:

  my @some_LOL = ([1,2],
  my int @array = @some_LOL;

I haven't got around to RFCing the more generic version (that all attributes
are inherited inside nested data types), but that would certainly be a nice

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