Utility Module

This XQuery Module contains various small utility and helper functions. Please note that some of the functions are used for internal query rewritings. They may be renamed or moved to other modules in future versions of BaseX.

Conventions

All functions in this module and errors are assigned to the http://basex.org/modules/util namespace, which is statically bound to the util prefix.

Function Items

util:function-annotations

Signatures	util:function-annotations($function as function(*)?) as map(xs:QName, xs:anyAtomicType*)
Summary	Returns the annotations of the specified $function in a map.
Examples	Returns an empty map: util:function-annotations(true#0) Returns a map with a single key Q{http://www.w3.org/2012/xquery}private and an empty sequence as value: declare %private function local:f() { 'well hidden' }; util:function-annotations(local:f#0)

Sequences

util:item-at

Signatures	util:item-at($sequence as item()*, $position as xs:double) as item()?
Summary	Returns the item from $sequence at the specified $position. Equivalent to $sequence[$position].
Examples	util:item-at(reverse(1 to 5), 1) returns 5. util:item-at(('a','b'), 0) returns an empty sequence.

util:item-range

Signatures	util:item-range($sequence as item()*, $first as xs:double, $last as xs:double) as item()*
Summary	Returns items from $sequence, starting at position $first and ending at $last. Equivalent to subsequence($sequence, $first, $last - $first + 1).
Examples	util:item-range(//item, 11, 20) returns all path results from (if available) position 11 to 20.

util:last-from

Signatures	util:last-from($sequence as item()*) as item()?
Summary	Returns last item of a $sequence. Equivalent to $sequence[last()].
Examples	util:last-from(reverse(1 to 100)) returns 1.

Changelog

The Module was introduced with Version 8.5.