I always wondered what assigning to $x[-1] would do in Perl.

So i started playing around with this...

Works:
$ perl -e 'my @arr=(1,2,3); $arr[-1]=4; print join " ", @arr, "\n";'
1 2 4
$

[download]

Doesn't work:
$ perl -e 'my @arr; $arr[-1]=4; print join " ", @arr, "\n";'
Modification of non-creatable array value attempted, subscript -1 at -
+e line 1.
$

[download]

Does this mean that perl does not create the array yet but merely creates a 'variable of type array' when doing my @array ?(kindof like Vector myVector; in java). It would only create the array and start allocating memory to it when you start inserting elements to that array ..


Jorg

"Do or do not, there is no try" -- Yoda

In reply to Re: Re: Fun With Spaceship by jorg
in thread Fun With Spaceship by japhy

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