I agree with your point -- this might be one of those modules that just "objectifies" something that's already pretty simple (so why bother?). Your alternative is a common, simple approach that is bound to be appropriate for the reviewer's main example -- comparing the output of "find" from two different machines -- because there won't be any duplications within a single set. But of course if one element happens to appear more than once in a single list, you get a false report about it being in both lists. This is easy to fix (in fact, fixing it makes the code simpler): 
my @ary1 = qw/1 2 3 4 5 4 6/;
my @ary2 = qw/5 6 7 8 7 9 10/;
my %h;
$h{$_} .= "a" for ( @ary1 );
$h{$_} .= "b" for ( @ary2 );
compare( "Only in ary1", "a\$", \%h );
compare( "Only in ary2", "^b", \%h );
compare( "Common to both", "ab", \%h );

sub compare {
    my ( $text, $regex, $hash ) = @_;
    print join "\n", $text, grep { $$hash{$_} =~ /$regex/ } keys %$has
+h;
    print "\n";
}

[download]

In reply to Re: alternative to List::Compare by graff
in thread List::Compare by McMahon

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.