Beware of that code!

With that code you push the reference in $AoA[0] to @AoA2 (let's say it is stored at $AoA2[0]). So if you change the data referenced by $AoA2[0] you will change the data also for @AoA1, because they ($AoA1[0] and $AoA2[0]) share the reference to the same data!

It may be that that is you desired behaviour, but it may be not...

#!/usr/bin/perl
# vi:ts=4 sw=4 et:
use strict;
use warnings;
use Data::Dumper;

my @AoA1 = (
    [ 1, 2, 3 ],
    [ qw( a b c ) ],
);

my @AoA2 = ();


$AoA2[0] = $AoA1[0];

# change the '1' in AoA2
$AoA2[0]->[0] = 0;

# check stored reference
print "\$AoA1[0]", $AoA1[0], $/;
print "\$AoA2[0]", $AoA2[0], $/;

# look what happened! AoA1 is changed!
print Dumper \@AoA1;

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In reply to Re^2: accessing element of array of arrays by linuxer
in thread accessing element of array of arrays by perlqs

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