On 10-06-06 10:49 AM, Philip Potter wrote:
On 6 June 2010 14:37, Shawn H Corey<[email protected]> wrote:
On 10-06-06 09:06 AM, Chas. Owens wrote:
But that is not the problem; autovivification will create the references:
perl -MData::Dumper -le '$c->[0]{a}; print Dumper $c'
But that is the problem. Autovivification should not happen for r-values,
only l-values.
I take it you mean it should only happen when you write to a location
($c->[3] = 'foo') not when you read from a location (print $c->[3]) ?
I would think that $c->[0]{a} is an lvalue by most definitions - it's
a value which can be written to. It's an lvalue even when on the right
side of an assignment.
Yes, although the names are taken from whether they appear on the left
or right of a simple assignment, what they are depends on whether a
value is assigned. In the Perl one-liner above, they are all r-values.
Now consider:
$c->[$a[$index]]{a} = $count++;
R-values in the above:
$c
$index
$a[$index]
'a'
$c->[$a[$index]]
$count
L-values:
$c->[$a[$index]]{a}
$count
As you can see, things can get complicated very quickly.
--
Just my 0.00000002 million dollars worth,
Shawn
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as it is about coding.
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