I have noticed an increase in the use of the __DATA__ token in the posts on PerlMonks. I understand that the data following the __DATA__ token is not loaded until requested which could be an advantage if you have a large amount of static data. However, I think it is true that same data can only be read once and only in a sequential manner which could be a disadvantage in certain situations. I suppose you could set the file pointer using seek and get a specific portion of data or re-read the data but that just doesn't sound good to me. With our declarations, the data is easily reusable in a random access manner but it gets loaded at the beginning whether it's needed later on or not.

I am curious what others think about the use of __DATA__ versus the use of our including any specific advantages/disadvantages to either way of doing it. The following examples don't have much data but it's the idea I'm interested in.

#!/usr/bin/perl -w

use strict;

our @data = ("a1","a2","a3","a4","a5","a6","a7","a8","a9","a0");

foreach (@data)
{
    print "$_\n";
}

exit;
[download]

Versus

#!/usr/bin/perl -w

use strict;

while (<DATA>)
{
    print "$_";
}

exit;


__DATA__
a1
a2
a3
a4
a5
a6
a7
a8
a9
a0
[download]

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