Difference between revisions of "Utility Module"

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(Created page with "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...")
 
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All functions in this module and errors are assigned to the <code><nowiki>http://basex.org/modules/util</nowiki></code> namespace, which is statically bound to the {{Code|util}} prefix.<br/>
 
All functions in this module and errors are assigned to the <code><nowiki>http://basex.org/modules/util</nowiki></code> namespace, which is statically bound to the {{Code|util}} prefix.<br/>
  
=Function Items=
+
=Functions=
 
 
==util:function-annotations==
 
 
 
{| width='100%'
 
|-
 
| width='120' | '''Signatures'''
 
|{{Func|util:function-annotations|$function as function(*)?|map(xs:QName, xs:anyAtomicType*)}}<br/>
 
|-
 
| '''Summary'''
 
|Returns the annotations of the specified {{Code|$function}} in a map.
 
|-
 
| '''Examples'''
 
|
 
* Returns an empty map:
 
<pre class="brush:xquery">
 
util:function-annotations(true#0)
 
</pre>
 
* Returns a map with a single key <code><nowiki>Q{http://www.w3.org/2012/xquery}private</nowiki></code> and an empty sequence as value:
 
<pre class="brush:xquery">
 
declare %private function local:f() { 'well hidden' };
 
util:function-annotations(local:f#0)
 
</pre>
 
|}
 
 
 
=Sequences=
 
  
 
==util:item-at==
 
==util:item-at==

Revision as of 21:22, 7 March 2016

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.

Functions

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.