index.field.config_id=config_id
index.field.expires=expires
index.field.url=url
index.field.doc_id=doc_id
index.field.id=_id
index.field.version=_version
index.field.seq_no=_seq_no
index.field.primary_term=_primary_term
index.field.lang=lang
index.field.has_cache=has_cache
index.field.last_modified=last_modified
index.field.anchor=anchor
index.field.segment=segment
index.field.role=role
index.field.boost=boost

    /** The key of the configuration. e.g. _seq_no */
    String INDEX_FIELD_seq_no = "index.field.seq_no";

    /** The key of the configuration. e.g. _primary_term */
    String INDEX_FIELD_primary_term = "index.field.primary_term";

    /** The key of the configuration. e.g. lang */
    String INDEX_FIELD_LANG = "index.field.lang";

    /** The key of the configuration. e.g. has_cache */

                if (seqNo != null) {
                    builder.setIfSeqNo(seqNo.longValue());
                }
                if (primaryTerm != null) {
                    builder.setIfPrimaryTerm(primaryTerm.longValue());
                }
                response = builder.execute().actionGet(fessConfig.getIndexIndexTimeout());
            }

		return FromArray(rval), nil
	case nil:
		return FromNull(), nil
	case Missing:
		return FromMissing(), nil
	}
	return nil, fmt.Errorf("Unhandled value type: %T", result)
}

func (e *PrimaryTerm) evalNode(r Record, tableAlias string) (res *Value, err error) {
	switch {
	case e.Value != nil:
		return e.Value.evalNode(r)
	case e.JPathExpr != nil:
		return e.JPathExpr.evalNode(r, tableAlias)