code: function identifyCommentType(tag) {
      var commentType = null;
      for (var tagName in tag) {
          if (tag.hasOwnProperty(tagName)) {
              switch (tagName) {
                  case exports.TAG_NAMES.API:
                  case exports.TAG_NAMES.METHOD:
                  case exports.TAG_NAMES.METHOD_SIGNATURE:
                  case exports.TAG_NAMES.METHOD_NAME:
                  case exports.TAG_NAMES.PARAM:
                  case exports.TAG_NAMES.RETURN:
                  case exports.TAG_NAMES.THROWS:
                      commentType = exports.COMMENT_TYPES.METHOD;
                      break;
                  case exports.TAG_NAMES.MODULE:
                  case exports.TAG_NAMES.REQUIRES:
                      commentType = exports.COMMENT_TYPES.MODULE;
                      break;
                  case exports.TAG_NAMES.CLASS:
                      commentType = exports.COMMENT_TYPES.TYPE;
                      break;
                  case exports.TAG_NAMES.VARIABLE_NAME:
                      commentType = exports.COMMENT_TYPES.VARIABLE;
                      break;
              }
          }
      }
  
      return commentType;
  }
docs: Try to identify the type of a comment from a comment tag.
  @param tag a tag
  @return {String} the type of the comment or null if not identified
  @private