Contributed by Anonymous Monk
on Mar 08, 2001 at 19:11 UTC
Q&A
> references
Description:
I create a hash where each element refers to an array:
$h{'one'} = [1,2,3];
I can access the individual array elements o.k.:
print "$h{'one'}[1]\n";
prints "2" as I expect.
Why can't I access the entire array as if it were a regular array?
What don't I understand here:
my @a = $h{'one'};
print "$a[1]\n";
doesn't do what I expect.
Answer: How do I refer to an element of a hash of arrays as an array
contributed by arturo
Since hash values can only be scalars, the value is a reference to an array.
That is, it's like a pointer.
(Try print "$h{'one'}\n" and see what you get.)
To get at the thing the reference points to, you need to explicitly dereference it.
To get at the array, do
my @a = @{ $h{one} };
By enclosing something in the @{ } construction, you're saying that you want the array to which that reference points.
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