This XQuery Module contains some utility and helper functions.
With Version 11, many functions have been removed in favor of new features of XQuery 4:
Conventions
All functions and errors in this module and errors are assigned to the http://basex.org/modules/util
namespace, which is statically bound to the util
prefix.
Conditions and Ranges
util:if
Signature
|
util:if(
$condition as item()*,
$then as item()*,
$else as item()* := ()
) as item()*
|
Summary
|
Alternative writing for the if/then/else expression:
- If the effective boolean value of
$condition is true, the $then branch will be evaluated.
- Otherwise,
$else will be evaluated. If the third argument is omitted, an empty sequence will be returned.
|
Examples
|
util:if(true(), 123, 456) returns 123 .
util:if(0, 'wrong!') returns an empty sequence.
|
util:count-within
Signature
|
util:count-within(
$sequence as item()*,
$min as xs:integer,
$max as xs:integer := ()
) as xs:boolean
|
Summary
|
Checks if the specified $sequence has at least $min and, optionally, at most $max items. Equivalent to:
let $count := count($sequence)
return $count >= $min and $count <= $max
|
Examples
|
util:count-within(('a', 'b', 'c'), 2) returns true .
util:count-within((1 to 1000000000)[. < 10], 3, 6) returns true .
|
util:range
Signature
|
util: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:range(//item, 11, 20) returns all path results from (if available) position 11 to 20.
|
Node Functions
util:ddo
Signature
|
util:ddo(
$nodes as node()*
) as node()*
|
Summary
|
Returns nodes in distinct document order: duplicate nodes will be removed, and the remaining nodes will be returned in document order. As results of path expressions are brought distinct document order before they are returned, the function is equivalent to:
$nodes/self::node()
|
util:root
Signature
|
util:root(
$nodes as node()*
) as document-node()*
|
Summary
|
Returns the document nodes of the specified $nodes . The path expression /abc is internally represented as util:root(.)/abc . Equivalent to:
$nodes ! /
|
util:strip-namespaces
Signature
|
util:strip-namespaces(
$node as node(),
$prefixes as xs:string* := ()
) as node()
|
Summary
|
Removes namespaces with the specified $prefixes from the supplied $node . An empty string can be supplied to remove the default namespace. If no prefixes are specified, all namespaces will be removed.
|
Examples
|
- Remove all namespaces from an element and its descendants:
util:strip-namespaces(<xml xmlns='uri' xmlns:prefix='uri2' prefix:name='value'><prefix:child/></xml>)
(: yields :)
<xml name='value'><child/></xml>
- Remove all default namespaces:
<xml xmlns='uri1'><child xmlns='uri2'/></xml>
=> util:strip-namespaces('')
|
Errors
Code
|
Description
|
negative
|
The specified number is negative.
|
Changelog
- Version 11.0
- Removed:
util:array-members
, util:array-values
, util:chars
, util:duplicates
, util:init
, util:intersperse
, util:item
, util:last
, util:map-entries
, util:map-values
, util:replicate
- Version 9.7
- Version 9.5
- Added:
util:intersperse
, util:within
, util:duplicates
, util:array-members
, util:array-values
, util:map-entries
, util:map-values
- Updated:
util:replicate
: Third argument added.
- Version 9.4
- Version 9.3
- Version 9.2
- Added:
util:chars
, util:init
- Updated:
util:item
, util:last
, util:range
renamed (before: util:item-at
, util:item-range
, util:last-from
)
- Version 9.1
- Version 9.0
The Module was introduced with Version 8.5.