I'm using Algorithm::Diff to keep track of proposed changes to documents. However if I have two proposed changes to the same document I want to be able to tell if the two changes overlap at all. If they don't I want to be able to merge the output of the results of the two different diffs into one set of changes.

As some sample code I have: 

#!/usr/bin/perl
use Algorithm::Diff qw(diff);
use Data::Dumper;
my $t1="This is the 1st lin\n This is the second line";
my $t2="This is the 1st line\n This is the second line`";
my $t3="This is the 1st lin\n This is the 2nd line`";
my @t1=split(//,$t1);
my @t2=split(//,$t2);
my @t3=split(//,$t3);
@diff=diff(\@t1,\@t2);
@diff2=diff(\@t1,\@t3);
print Dumper(@diff);
print "\n--------\n";
print Dumper(@diff2);

[download]
I get the following printed out for the differences between $t1 and $t2 
$VAR1 = [
          [
            '+',
            19,
            'e'
          ]
        ];
$VAR2 = [
          [
            '+',
            45,
            '`'
          ]
        ];

[download]
Here is the computed difference between $t1 and $t3 
$VAR1 = [
          [
            '-',
            33,
            's'
          ],
          [
            '-',
            34,
            'e'
          ],
          [
            '-',
            35,
            'c'
          ],
          [
            '-',
            36,
            'o'
          ],
          [
            '+',
            33,
            2
          ]
        ];
$VAR2 = [
          [
            '+',
            41,
            '`'
          ]
        ];

[download]
How can I merge the two differences into one that can be applied to the original while verifying that the changes aren't conflicting. </CODE>

vroom | Tim Vroom | vroom@cs.hope.edu

In reply to Question about Algorithm::Diff by vroom

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.