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{{Version|8.1}}: Arrays are now based on an efficient [http://en.wikipedia.org/wiki/Finger_tree Finger Tree] implementation. An ''array'' is a function that associates a set of positions, represented as positive integer keys, with values. The first position in an array is associated with the integer {{Code|1}}. The values of an array are called its members. In the type hierarchy, array has a distinct type, which is derived from function. In BaseX, arrays (as well as sequences) are based on an efficient [http://en.wikipedia.org/wiki/Finger_tree Finger Tree] implementation.
for let $map in maps := (
In BaseX, The {{Code|adaptive}} is used as the new default serialization method. It provides a intuitive textual representation for all XDM types, including maps and arrays, functions, attributes, and namespaces. All items will be separated using by the value of the {{Code|item-separator}} parameter, or which by default is a newline if no value character. It is specifiedutilized by the functions <code>[[Profiling Module#prof:dump|prof:dump]]</code> and <code>[http://www.w3.org/TR/xpath-functions-31/#func-trace fn:trace]</code>. Example:
id="id0"xs:token("abc"),map {
function fn:true#0
[[Category:XQuery]]
→fn:sort
This article is part of the [[XQuery|XQuery Portal]].
It summarizes the new features of the [http://www.w3.org/TR/xquery-31/ XQuery 3.1] Working Draftand[http://www.w3.org/TR/xpath-functions-31/ XQuery 3.1 Functions and Operators] specifications
that are already supported by BaseX.
Please note that not all of the features that are listed on this page are already
found in the official specification documents today. You can check out the
[https://www.w3.org/Bugs/Public/ W3 Bugzilla Tracker] to find out more about the
most recently added features.
=Maps=
=Arrays=
Arrays can be constructed in two ways. With the square bracket notation, the comma serves as delimiter:
=Lookup Operator=
The lookup operator provides some syntactic sugar to access values of maps or array members at a specified position. It is introduced by the question mark ({{Code|?}}) and followed by a specifier. The specifier can be:
# A wildcard {{Code|*}},
<pre class="brush:xquery">
map { 'name': 'Guðrún', 'city': 'Reykjavík' },
map { 'name': 'Hildur', 'city': 'Akureyri' }
)
return $mapmaps[?name = 'Hildur'] ?city
</pre>
The syntax makes nested function calls more readable, as it is easy to see if parentheses are balanced.
=String Constructor=
The string constructor has been inspired by [https://en.wikipedia.org/wiki/Here_document here document] literals of the Unix shell and script languages. It allows you to generate strings that contain various characters that would otherwise be interpreted as XQuery delimiters.
The string constructors syntax uses two backticks and a square bracket for opening and closing a string:
<pre class="brush:xquery">
(: Returns "This is a 'new' & 'flexible' syntax." :)
``["This is a 'new' & 'flexible' syntax."]``
</pre>
XQuery expressions can be embedded via backticks and a curly bracket. The evaluated results will be separated with spaces, and all strings will eventually be concatenated:
<pre class="brush:xquery">
(: Returns »Count 1 2 3, and I will be there.« :)
let $c := 1 to 3
return ``[»Count `{ $c }`, and I will be there.«]``</pre>
=Serialization=
==Adaptive Serialization==
<pre class="brush:xquery">
declare option output:method 'adaptive';
<element id='id0'/>/@id,
xs:token("abc"),
map { 'key': 'value' },
true#0
<pre class="brush:xml">
"key": "value"
}
</pre>
</pre>
===fn:json-docsdoc===
; Signatures
<pre class="brush:xquery">
json-doc("http://ip.jsontest.com/")('ip') (: returns your IP address :)
</pre>
===fn:json-to-xml===
; Signatures
* <code>fn:json-to-xml($string as xs:string?) as node()?</code>
Converts a JSON string to an XML node representation. The allowed options can be looked up in the [http://www.w3.org/TR/xslt-30/#func-json-to-xml specification].
<pre class="brush:xquery">
json-to-xml('{ "message": "world" }')
(: result:
<map xmlns="http://www.w3.org/2005/xpath-functions">
<string key="message">world</string>
</map> :)
</pre>
===fn:xml-to-json===
; Signatures
* <code>fn:xml-to-json($node as node()?) as xs:string?</code>
Converts an XML node, whose format conforms to the results created by [[#fn:json-to-xml|fn:json-to-xml]], to a JSON string representation. The allowed options can be looked up in the [http://www.w3.org/TR/xslt-30/#func-xml-to-json specification].
<pre class="brush:xquery">
(: returns "JSON" :)
xml-to-json(<string xmlns="http://www.w3.org/2005/xpath-functions">JSON</string>)
</pre>
==fn:sort==
{{Mark|Updated with Version 8.6:}} Collation argument was inserted between first and second argument.
; Signatures
* <code>fn:sort($input as item()*) as item()*</code>
* <code>fn:sort($input as item()*, $collation as xs:string?) as xs:anyAtomicType*)) as item()*</code>* <code>fn:sort($input as item()*, $collation as xs:string?, $key as function(item()*) as xs:anyAtomicType*)) as item()*</code>
Returns a new sequence with sorted {{Code|$input}} items, using an optional {{Code|$collation}}. If a sort {{Code|$key}} function is givensupplied, it will be applied on all items. The items of the resulting values will be sorted using the semantics of the {{Code|lt}} expression.
<pre class="brush:xquery">
sort(reverse(1 to 3)) (: yields 1, 2, 3 :),reverse(sort(1 to 3)) (: returns the sorted order in descending order :),sort((3, -2, 1), (), abs#1) (: yields 1, -2, 3 :),sort((1,2,3), (), function($x) { -$x }) (: yields 3, 2, 1 :),sort((1, 'a')) (: yields an error, as strings and integers cannot be compared :)
</pre>
fn:trace(<xml/>)/node() (: returns the debugging output "<xml/>" :)
</pre>
==fn:string-join==
The type of the first argument is now <code>xs:anyAtomicType*</code>, and all items will be implicitly cast to strings:
<pre class="brush:xquery">
fn:string-join(1 to 3) (: yields the string "123" :)
</pre>
==fn:default-language==
Returns the default language used for formatting numbers and dates. BaseX always returns {{Code|en}}.
=Binary Data=
(: returns 0 (both strings are compared as equal) :)
compare('a-b', 'ab', 'http://www.w3.org/2013/collation/UCA?alternate=shifted')
</pre>
=Enclosed Expressions=
''Enclosed expression'' is the syntactical term for the expressions that are specified inside a function body, try/catch clauses, node constructors and some other expressions. In the following example expressions, it’s the empty sequence:
<pre class="brush:xquery">
declare function local:x() { () };
try { () } catch * { () },
element x { () },
text { () }
</pre>
With XQuery 3.1, the expression can be omitted. The following query is equivalent to the upper one:
<pre class="brush:xquery">
declare function local:x() { };
try { } catch * { },
element x { }
text { }
</pre>
=Changelog=
;Version 8.6
* Updated: Collation argument was inserted between first and second argument.
;Version 8.4
* Added: [[#String Constructors|String Constructors]], [[#fn:default-language|fn:default-language]], [[#Enclosed Expressions|Enclosed Expressions]]
* Updated: [[#Adaptive Serialization|Adaptive Serialization]], [[#fn:string-join|fn:string-join]]
;Version 8.2
* Added: [[#fn:json-to-xml|fn:json-to-xml]], [[#fn:xml-to-json|fn:xml-to-json]].
;Version 8.1
* Updated: arrays are now based on an efficient a [http://en.wikipedia.org/wiki/Finger_tree Finger Tree] implementation.
Introduced with Version 8.0.
