# File lib/rubygems/commands/dependency_command.rb, line 34
      def execute
        specs = {}
        srcindex = SourceIndex.from_installed_gems
        options[:args] << '.' if options[:args].empty?
        options[:args].each do |name|
          speclist = srcindex.search(name, options[:version])
          if speclist.empty?
            say "No match found for #{name} (#{options[:version]})"
          else
            speclist.each do |spec|
              specs[spec.full_name] = spec
            end
          end
        end
        reverse = Hash.new { |h, k| h[k] = [] }
        if options[:reverse_dependencies]
          specs.values.each do |spec|
            reverse[spec.full_name] = find_reverse_dependencies(spec, srcindex)
          end
        end
        if options[:pipe_format]
          specs.values.sort.each do |spec|
            unless spec.dependencies.empty?
              spec.dependencies.each do |dep|
                puts "#{dep.name} --version '#{dep.version_requirements}'"
              end
            end
          end     
        else
          response = ''
          specs.values.sort.each do |spec|
            response << print_dependencies(spec)
            unless reverse[spec.full_name].empty?
              response << "  Used by\n"
              reverse[spec.full_name].each do |sp, dep|
                response << "    #{sp} (#{dep})\n"
              end
            end
            response << "\n"
          end
          say response
        end
      end