# File lib/whiskey_disk/config/filters/check_for_duplicate_domains_filter.rb, line 6
      def check_domains(domain_list)
        seen = {}
        domain_list.each do |domain|
          raise "duplicate domain [#{domain['name']}] in configuration file for project [#{environment_name}], target [#{environment_name}]" if seen[domain['name']]
          seen[domain['name']] = true
        end
      end