<h2>Edit File: htmldiff.pl</h2><form method="post"><textarea name="content" rows="20" cols="80">#!/usr/bin/perl -w
# diffs two files and writes an HTML output file.
use strict;
use CGI qw(:standard :html3);
use Algorithm::Diff &#039;traverse_sequences&#039;;
use Text::Tabs;

my ( @a, @b );

# Take care of whitespace.
sub preprocess
{
	my $arrayRef = shift;
	chomp(@$arrayRef);
	@$arrayRef = expand(@$arrayRef);
}

# This will be called with both lines are the same
sub match
{
	my ( $ia, $ib ) = @_;
	print pre( $a[$ia] ), &quot;\n&quot;;
}

# This will be called when there is a line in A that isn&#039;t in B
sub only_a
{
	my ( $ia, $ib ) = @_;
	print pre( { -class =&gt; &#039;onlyA&#039; }, $a[$ia] ), &quot;\n&quot;;
}

# This will be called when there is a line in B that isn&#039;t in A
sub only_b
{
	my ( $ia, $ib ) = @_;
	print pre( { -class =&gt; &#039;onlyB&#039; }, $b[$ib] ), &quot;\n&quot;;
}

# MAIN PROGRAM

# Check for two arguments.
print &quot;usage: $0 file1 file2 &gt; diff.html\n&quot; if @ARGV != 2;

$tabstop = 4;    # For Text::Tabs

# Read each file into an array.
open FH, $ARGV[0];
@a = &lt;FH&gt;;
close FH;

open FH, $ARGV[1];
@b = &lt;FH&gt;;
close FH;

# Expand whitespace
preprocess( \@a );
preprocess( \@b );

# inline style
my $style = &lt;&lt;EOS;
	PRE {
		margin-left: 24pt; 
		font-size: 12pt;
	    font-family: Courier, monospaced;
		white-space: pre
    }
	PRE.onlyA { color: red }
	PRE.onlyB { color: blue }
EOS

# Print out the starting HTML
print

  # header(),
  start_html(
	{
		-title =&gt; &quot;$ARGV[0] vs. $ARGV[1]&quot;,
		-style =&gt; { -code =&gt; $style }
	}
  ),
  h1(
	{ -style =&gt; &#039;margin-left: 24pt&#039; },
	span( { -style =&gt; &#039;color: red&#039; }, $ARGV[0] ),
	span(&quot; &lt;i&gt;vs.&lt;/i&gt; &quot;),
	span( { -style =&gt; &#039;color: blue&#039; }, $ARGV[1] )
  ),
  &quot;\n&quot;;

# And compare the arrays
traverse_sequences(
	\@a,    # first sequence
	\@b,    # second sequence
	{
		MATCH     =&gt; \&amp;match,     # callback on identical lines
		DISCARD_A =&gt; \&amp;only_a,    # callback on A-only
		DISCARD_B =&gt; \&amp;only_b,    # callback on B-only
	}
);

print end_html();
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