A couple of thoughts:

1) As a stylistic preference, whenever I construct a nested data variable in perl, I always start with a scalar variable at the top, like '$dataroot'. I like the way it looks and it's flexible, since a scalar can hold a reference to anything. You'll notice that Data::Dumper does the same thing when it spits out ($VAR1 $VAR2 etc..) as the topmost 'container' of the output.

2) Using the style mentioned above helps me focus more on the *meaning* of what it is I am really storing, helps keeps things readable. Given this style, your example becomes this slightly different code ... 

use strict;
use warnings;

my $chapters = [
    {
        title   => 'Basic',
        page    => [
            { paragraph => 'lesson1'},
            { paragraph => 'lesson2'},
        ],
    },
    {
        title   => 'Advanced',
        page    => [
            { paragraph => 'lesson3'},
            { paragraph => 'lesson4'},
        ],
    },
];

### since we started with a scalar to hold
    ### an anonymous array ref, we have to
    ### use the little 'arrow' notation

print   $chapters->[0]{title};  ### basic
print   "\n---------------\n";

print   $chapters->[1]{title};  ### advanced
print   "\n---------------\n";

print   $chapters->[1]{page}[0]{paragraph}; ### lesson3
print   "\n---------------\n";

print   $chapters->[1]{page}[1]{paragraph}; ### lesson4
print   "\n---------------\n";

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In reply to Re: Accessing an AoHoAoH by dimar
in thread Accessing an AoHoAoH by bradcathey

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