Hello Monks, I have a working script to find the difference between two sets of strings. I found some good documentation and examples of traverse sequences but it has some code in it that I don't understand. It works, but I would like to know what is going on. Here is the code snippet: 
    my @old = split(/\s+/, $old);
    my @new = split(/\s+/, $new);

    traverse_sequences(\@old, \@new, 
    {
       MATCH => sub { print OUTPUT shift(@old)."\n"},
       DISCARD_A => sub { print OUTPUT "<strong><font color=red>".@old
+->[shift]."</font></strong>\n"},
        DISCARD_B => sub { print "<strong><font color=blue>".@new->[sh
+ift, shift]."</font></strong>\n"},
    }
    );

[download]
Basically just feeding in two string array references, but the @new->shift, shift is what I do not understand. At first I thought it is equivalent to shift(@new).shift(@new) but it is not. @old->shift seems similar to shift(@old) but looking at it closer, it yields different results as well... Thank you for any wisdom you can share!

In reply to Traverse Sequences in Algorithm::Diff module by dPerl

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