private static String computePrefix(TemplateImpl template, String argument) {
    String key = template.getKey();
    if (argument == null) {
      return key;
    }
    if (key.length() > 0 && Character.isJavaIdentifierPart(key.charAt(key.length() - 1))) {
      return key + ' ' + argument;
    }
    return key + argument;
  }
private static String computePrefix(TemplateImpl template, String argument)