fn.headfn.headfnhead/apidoc/8.0/fn:head.xml
Returns the first item in a sequence.
For more details, see
XPath 3.0 Functions and Operators.
The function value.
seqValueIterator
A sequence of function values (as a ValueIterator). If you pass in a
single value,
it is treated as a ValueIterator with that single item; therefore, if you
pass in an array, the function will return the array.
If you mean to check the values of each item in the array, then
you can call xdmp.arrayValues
on the array.
argValueIteratorValueIterator