This functions returns all members of all arrays of the supplied sequence.
members($a as item*) as item*
Example 183. Retrieving the members of all supplied arrays, ignoring non-arrays.
let $planets := ( "foo", { "foo" : "bar "}, [ "mercury", "venus", "earth", "mars" ], [ 1, 2, 3 ])
return members($planets)
Result (run with Zorba): mercury venus earth mars 1 2 3