class Slim::Splat::Builder

def attr(name, value)
  if name =~ INVALID_ATTRIBUTE_NAME_REGEX
    raise InvalidAttributeNameError, "Invalid attribute name '#{name}' was rendered"
  end
  if @attrs[name]
    if delim = @options[:merge_attrs][name]
      @attrs[name] = @attrs[name].to_s + delim + value.to_s
    else
      raise("Multiple #{name} attributes specified")
    end
  else
    @attrs[name] = value
  end
end