Could not execute XQUERY declare function local:go
      ( $parentItem
      )
      { ( $parentItem
        , for-each( $parentItem/child::*
                  , local:go( ?)
                  )
        )
      } ;
      
     
let    $source     := 
document {
  <xml>
    <text>Hello</text>
    <text>World</text>
  </xml>
         }
return local:go( $source)
:
Improper use? Potential bug? Your feedback is welcome:
Contact: basex-talk@mailman.uni-konstanz.de
Version: BaseX 8.0 beta b8c7fc0
Java: Oracle Corporation, 1.7.0_55
OS: Windows Vista, x86
Stack Trace: 
java.lang.NullPointerException
	at org.basex.query.QueryParser.functionCall(QueryParser.java:2315)
	at org.basex.query.QueryParser.primary(QueryParser.java:2068)
	at org.basex.query.QueryParser.postfix(QueryParser.java:2010)
	at org.basex.query.QueryParser.step(QueryParser.java:1890)
	at org.basex.query.QueryParser.path(QueryParser.java:1806)
	at org.basex.query.QueryParser.value(QueryParser.java:1694)
	at org.basex.query.QueryParser.unary(QueryParser.java:1681)
	at org.basex.query.QueryParser.cast(QueryParser.java:1659)
	at org.basex.query.QueryParser.castable(QueryParser.java:1647)
	at org.basex.query.QueryParser.treat(QueryParser.java:1635)
	at org.basex.query.QueryParser.instanceoff(QueryParser.java:1623)
	at org.basex.query.QueryParser.intersect(QueryParser.java:1602)
	at org.basex.query.QueryParser.union(QueryParser.java:1576)
	at org.basex.query.QueryParser.multiplicative(QueryParser.java:1560)
	at org.basex.query.QueryParser.additive(QueryParser.java:1545)
	at org.basex.query.QueryParser.range(QueryParser.java:1534)
	at org.basex.query.QueryParser.stringConcat(QueryParser.java:1520)
	at org.basex.query.QueryParser.ftContains(QueryParser.java:1494)
	at org.basex.query.QueryParser.comparison(QueryParser.java:1476)
	at org.basex.query.QueryParser.modify(QueryParser.java:1457)
	at org.basex.query.QueryParser.and(QueryParser.java:1443)
	at org.basex.query.QueryParser.or(QueryParser.java:1429)
	at org.basex.query.QueryParser.single(QueryParser.java:994)
	at org.basex.query.QueryParser.argumentList(QueryParser.java:2353)
	at org.basex.query.QueryParser.functionCall(QueryParser.java:2303)
	at org.basex.query.QueryParser.primary(QueryParser.java:2068)
	at org.basex.query.QueryParser.postfix(QueryParser.java:2010)
	at org.basex.query.QueryParser.step(QueryParser.java:1890)
	at org.basex.query.QueryParser.path(QueryParser.java:1806)
	at org.basex.query.QueryParser.value(QueryParser.java:1694)
	at org.basex.query.QueryParser.unary(QueryParser.java:1681)
	at org.basex.query.QueryParser.cast(QueryParser.java:1659)
	at org.basex.query.QueryParser.castable(QueryParser.java:1647)
	at org.basex.query.QueryParser.treat(QueryParser.java:1635)
	at org.basex.query.QueryParser.instanceoff(QueryParser.java:1623)
	at org.basex.query.QueryParser.intersect(QueryParser.java:1602)
	at org.basex.query.QueryParser.union(QueryParser.java:1576)
	at org.basex.query.QueryParser.multiplicative(QueryParser.java:1560)
	at org.basex.query.QueryParser.additive(QueryParser.java:1545)
	at org.basex.query.QueryParser.range(QueryParser.java:1534)
	at org.basex.query.QueryParser.stringConcat(QueryParser.java:1520)
	at org.basex.query.QueryParser.ftContains(QueryParser.java:1494)
	at org.basex.query.QueryParser.comparison(QueryParser.java:1476)
	at org.basex.query.QueryParser.modify(QueryParser.java:1457)
	at org.basex.query.QueryParser.and(QueryParser.java:1443)
	at org.basex.query.QueryParser.or(QueryParser.java:1429)
	at org.basex.query.QueryParser.single(QueryParser.java:994)
	at org.basex.query.QueryParser.expr(QueryParser.java:971)
	at org.basex.query.QueryParser.parenthesized(QueryParser.java:2286)
	at org.basex.query.QueryParser.primary(QueryParser.java:2059)
	at org.basex.query.QueryParser.postfix(QueryParser.java:2010)
	at org.basex.query.QueryParser.step(QueryParser.java:1890)
	at org.basex.query.QueryParser.path(QueryParser.java:1806)
	at org.basex.query.QueryParser.value(QueryParser.java:1694)
	at org.basex.query.QueryParser.unary(QueryParser.java:1681)
	at org.basex.query.QueryParser.cast(QueryParser.java:1659)
	at org.basex.query.QueryParser.castable(QueryParser.java:1647)
	at org.basex.query.QueryParser.treat(QueryParser.java:1635)
	at org.basex.query.QueryParser.instanceoff(QueryParser.java:1623)
	at org.basex.query.QueryParser.intersect(QueryParser.java:1602)
	at org.basex.query.QueryParser.union(QueryParser.java:1576)
	at org.basex.query.QueryParser.multiplicative(QueryParser.java:1560)
	at org.basex.query.QueryParser.additive(QueryParser.java:1545)
	at org.basex.query.QueryParser.range(QueryParser.java:1534)
	at org.basex.query.QueryParser.stringConcat(QueryParser.java:1520)
	at org.basex.query.QueryParser.ftContains(QueryParser.java:1494)
	at org.basex.query.QueryParser.comparison(QueryParser.java:1476)
	at org.basex.query.QueryParser.modify(QueryParser.java:1457)
	at org.basex.query.QueryParser.and(QueryParser.java:1443)
	at org.basex.query.QueryParser.or(QueryParser.java:1429)
	at org.basex.query.QueryParser.single(QueryParser.java:994)
	at org.basex.query.QueryParser.expr(QueryParser.java:963)
	at org.basex.query.QueryParser.enclosed(QueryParser.java:952)
	at org.basex.query.QueryParser.functionDecl(QueryParser.java:906)
	at org.basex.query.QueryParser.prolog2(QueryParser.java:421)
	at org.basex.query.QueryParser.parseMain(QueryParser.java:194)
	at org.basex.query.QueryContext.parseMain(QueryContext.java:215)
	at org.basex.query.QueryProcessor.parse(QueryProcessor.java:59)
	at org.basex.core.cmd.AQuery.parse(AQuery.java:145)
	at org.basex.core.cmd.AQuery.updating(AQuery.java:159)
	at org.basex.core.cmd.AQuery.updating(AQuery.java:293)
	at org.basex.gui.GUI.exec(GUI.java:403)
	at org.basex.gui.GUI.access$500(GUI.java:41)
	at org.basex.gui.GUI$8.run(GUI.java:361)