glob is perhaps the prettiest solution, but it isn't recommended for large sets, since all combinations will be generated before any are returned. A recursive solution is better - something like the following: 
sub comb {
    my $s = shift;
    if (@_ == 1) { print "$s$_\n" for @{$_[0]}; return; }
    comb("$s$_",@_) for @{shift()};
}
comb '',[qw(a b c)],[qw(1 2 3)],[qw(- + *)];

[download]
Where you can change this line to do whatever you want with the combination: 
    if (@_ == 1) { dowhatever("$s$_") for @{$_[0]}; return; }

[download]
BrowserUK's solution is somewhat neater, but it's more a pull down approach, where all combinations are returned at once, rather than a push up approach, where only one combination is worked on at a time. You might as well use glob if you're going that route.

In reply to Re: cartesian product preserving order by TedPride
in thread cartesian product preserving order by Anonymous Monk

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.