# File lib/mime/types.rb, line 676
    def add(*types)
      types.each do |mime_type|
        if mime_type.kind_of? MIME::Types
          add(*mime_type.defined_types)
        else
          if @type_variants.include?(mime_type.simplified)
            if @type_variants[mime_type.simplified].include?(mime_type)
              warn "Type #{mime_type} already registered as a variant of #{mime_type.simplified}." unless defined? MIME::Types::STARTUP
            end
          end
          add_type_variant(mime_type)
          index_extensions(mime_type)
        end
      end
    end