Filter out a set of tags based on their unique text contents

xmluniq

#!/usr/bin/env perl

use strict;
use warnings;
use 5.10.0;

#Let you define the --tag=rule on the command line
use Getopt::Long;

#Depends on the Mojo DOM because its light weight and nice to use
use Mojo::DOM;

my $tag;

GetOptions ('tag|t=s' => \$tag);

#Get a DOM for the XML, change <DATA> to <> for command line use
my $dom = Mojo::DOM->new(do { local $/; <DATA> });
#Map all the tags to key->val hash where the unique keys are the compacted text from each tag mapping to the last seen tag
my %unique_tags = map {my $u=$_->text; $u=~s/\s+/_/g; $u => $_} $dom->find($tag)->each;
#Print back out the tags we slurped for each unique value
print join "\n", values %unique_tags;

__DATA__
<?xml version="1.0"?>
<rule>
    something goes here whoa
</rule>
<rule>
    something goes there
</rule>
<rule>
        something goes here whoa
</rule>
<rule>
  something goes there
</rule>