Re: question on reference to array slice

Rick wrote:

In C we can store a set of pointers which point to different arrays
into an array of pointer. This way we could fast access different
array by looking it up in this pointer array. Is there anyway to do
this in Perl. I've been trying different things and no luck so far.

LIke:
@nums = (1 .. 20);

I want to store the reference to @nums[1..10] into $data[0], and the
reference to @nums[11:20] into $data[1], so that I could visit, for
example, the second set of @nums by something like $data[1][5] to get
15.

$ perl -le'
@nums = 1 .. 20;
print "@nums";
$data[ 0 ] = [ \@nums[ 0 .. 9 ] ];
$data[ 1 ] = [ \@nums[ 10 .. 19 ] ];
print ${ $data[ 1 ][ 5 ] };
${ $data[ 1 ][ 5 ] } = 0;
print "@nums";
'
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
16
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 0 17 18 19 20




John
--
Perl isn't a toolbox, but a small machine shop where you
can special-order certain sorts of tools at low cost and
in short order. -- Larry Wall
.

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