OrientDB select flatten test

gistfile1.txt

orientdb> select from eventprofile

----+-----+----+-------+----+-----
#   |@RID |out_|EventID|Type|in_
----+-----+----+-------+----+-----
0   |#12:0|[3] |#11:0  |Job |#11:0
----+-----+----+-------+----+-----

1 item(s) found. Query executed in 0.024 sec(s).

orientdb> select out() from eventprofile

----+-----+----
#   |@RID |out
----+-----+----
0   |#-2:1|[3]
----+-----+----

1 item(s) found. Query executed in 0.018 sec(s).

orientdb> select out().Title from eventprofile

----+-----+----
#   |@RID |out
----+-----+----
0   |#-2:1|[3]
----+-----+----

1 item(s) found. Query executed in 0.023 sec(s).

orientdb> select flatten(out().Title) from eventprofile

----+------+--------------
#   |@RID  |value
----+------+--------------
0   |#-1:-1|Profile item 1
1   |#-1:-1|Profile item 2
2   |#-1:-1|Profile item 3
----+------+--------------

3 item(s) found. Query executed in 0.02 sec(s).

orientdb> select flatten(out().Title)[0] from eventprofile

Error: com.orientechnologies.orient.core.sql.OCommandSQLParsingException: Error on parsing command at position #0: Error on parsing command at position #0: Erro
r on reading parameters in: flatten(out().Title)[0]
orientdb> select first(flatten(out().Title)) from eventprofile

Error: com.orientechnologies.orient.core.sql.OCommandSQLParsingException: Error on parsing command at position #0: Error on parsing command at position #0: No f
unction for name FLATTEN, available names are : [COALESCE,GREMLIN,INV,DIJKSTRA,MAX,IFNULL,OUTV,SET,COUNT,MIN,SUM,LIST,INE,UNION,IF,BOTHE,DISTANCE,INTERSECT,IN,S
HORTESTPATH,LABEL,OUT,EVAL,SYSDATE,AVG,DECODE,MAP,OUTE,BOTH,BOTHV,FORMAT,LAST,DIFFERENCE,DATE,DISTINCT,ENCODE,FIRST]