Algorithm::Diff will operate on array elements. I use it to colorize differences inside lines.

If you will post some test cases, I can show you how it works.

Here's my simple colorizer, if that helps.

#!/usr/bin/perl

use Algorithm::Diff qw(traverse_sequences);
use Term::ANSIColor;
use strict;
use warnings;

my @from = split //, shift // 'this is the left string';
my @to = split //, shift // 'this is the right string';

traverse_sequences( \@from, \@to,
  {
  MATCH     => sub {print $from[shift()]},
  DISCARD_A => sub {print color('red'), $from[shift()], color 'reset'}
+,
  DISCARD_B => sub {print color('green'), $to[pop()], color 'reset'},
  } );
print "\n";
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