There are probably many ways to do this. Chances are there is some whizzy one-liner using Quantum::Superpositions or some such - but I haven't had time to look.

There are 2n-1 possibilities (where n is the length of your input array) and that suggested (to me) looking at the binary digits of each number from 1 to 2n-1. That's what this solution does. It probably isn't the most elegant, and I suspect it is not the most efficient either.

use strict;
use Data::Dumper;

my @firstArray = ( "item1", "item2", "item3" );

my $n = @firstArray;
my @results;

for my $i (1..2**$n-1) {
    my @selection;
    for my $j (0..$n-1) {
        if ($i & 2**$j) {
            push @selection, $firstArray[$j];
        }
    }
    push @results, \@selection;
}

print Dumper(\@results);

[download]
s^^unp(;75N=&9I<V@`ack(u,^;s|\(.+\`|"$`$'\"$&\"\)"|ee;/m.+h/&&print$&

In reply to Re: array logic by muntfish
in thread array logic by rsiedl

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.