in reply to dereference array

timestamps is a hash containing at least one element that is an array reference. The array reference contains 5 elements containing array references. That is a horrible way to describe the structure so lets look at some code ways of dealing with it

use strict;
use warnings;

my %timestamps = (
    x => [
        ['2013-08-18T20:43:40Z'],
        ['2013-08-18T20:43:12Z'],
    ]
);
my $page = 'x';
my @edits = @{$timestamps{$page}};

for my $stamps (@edits) {
    for my $stamp (@$stamps) {
        print "a: $stamp\n";
    }
}

print "b: $edits[0][0]\n";
print "b: $edits[1][0]\n";
print "c: $timestamps{x}[0][0]\n";
print "c: $timestamps{x}[1][0]\n";

[download]

Prints:

a: 2013-08-18T20:43:40Z
a: 2013-08-18T20:43:12Z
b: 2013-08-18T20:43:40Z
b: 2013-08-18T20:43:12Z
c: 2013-08-18T20:43:40Z
c: 2013-08-18T20:43:12Z

[download]

I've only populated two of the time stamps, but that should serve to see how things hand together. Note the {} to access the hash elements and the [] to access the array elements, and that you can concatenate them as you like for whatever structure you have.

True laziness is hard work

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Re^2: dereference array
by natxo (Scribe) on Dec 03, 2013 at 13:50 UTC
    I absolutely agree with you that this is a horrible way to get the structure.

    The original problem was getting the recent changes from a mediawiki site. I use the excellent mod:MediaWiki::Bot module to retrieve the info using the Mediawiki API.

    What you get is then an array of hashes with this structure: 

    $VAR50 = {
           'revid' => 174,
           'ns' => 0,
           'comment' => '',
           'timestamp' => '2013-04-01T12:30:28Z',
           'user' => 'user',
           'title' => 'page title',
           'type' => 'edit',
           'pageid' => 50,
           'old_revid' => 173,
           'rcid' => 180
         };

    [download]
    But I then need to put it all together per user: pages edited, number of edits, etc. It would be much easier if I had database access but that is a no-no Thanks for taking the time to look into this.
[reply]
[d/l]

      Have you looked at DBD::SQLite? It's completely stand alone - just install the module and you've got the whole thing. Maybe the advice in Yes, even you can use CPAN may help too?

      True laziness is hard work
[reply]
        That is something I had not thought of, self contained sql. Nice, I'll look into it.
[reply]

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