Difference between revisions of "XQuery 4.0"

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(Created page with "This article is part of the XQuery Portal. It provides a summary of the most important features of the [https://qt4cg.org/specifications/xpath-functions-40/Overview...")
 
 
(4 intermediate revisions by the same user not shown)
Line 29: Line 29:
 
=Arrow map operator=
 
=Arrow map operator=
  
−
<p>
+
<p style="white-space: pre-wrap;padding: 1em; border: 1px solid #eaecf0; background-color: #f8f9fa; color: #000; font-family: monospace;">"The cat sat on the mat"
−
<code>
+
=> tokenize()
−
"The cat sat on the mat"<br/>
+
<span style="color:#C00000">=!></span> concat(".")
−
=> tokenize()<br/>
+
<span style="color:#C00000">=!></span> upper-case()
−
<span style="color:#C00000">=!></span> concat(".")<br/>
+
=> string-join(" ")
−
<span style="color:#C00000">=!></span> upper-case()<br/>
 
−
=> string-join(" ")
 
−
</code>
 
 
</p>
 
</p>
  
Line 60: Line 57:
  
 
<p><code>fn:iterate-while($number, <span style="color:#C00000">fn { . </span> < 100 <span style="color:#C00000">}</span>, <span style="color:#C00000">fn { . </span> * <span style="color:#C00000">. }</span>)</code></p>
 
<p><code>fn:iterate-while($number, <span style="color:#C00000">fn { . </span> < 100 <span style="color:#C00000">}</span>, <span style="color:#C00000">fn { . </span> * <span style="color:#C00000">. }</span>)</code></p>
 +
 +
=Optional arguments=
 +
 +
<p style="white-space: pre-wrap;padding: 1em; border: 1px solid #eaecf0; background-color: #f8f9fa; color: #000; font-family: monospace;">declare function strings:get(
 +
  $value,
 +
  $default <span style="color:#C00000">:= "EMPTY"</span>
 +
) {
 +
  $value otherwise $default
 +
}
 +
strings:get('john')
 +
</p>
 +
 +
=Keyword arguments=
 +
 +
<p style="white-space: pre-wrap;padding: 1em; border: 1px solid #eaecf0; background-color: #f8f9fa; color: #000; font-family: monospace;">declare function coordinates(
 +
    $x := 0,
 +
    $y := 0
 +
  ) {
 +
    map { "x" : $x, "y" : $y }
 +
  }
 +
  coordinates(<span style="color:#C00000">y :=</span> 123)
 +
</p>
 +
 +
=String templates=
 +
 +
<p><code><span style="color:#C00000">`</span>Name: <span style="color:#C00000">{</span> $name <span style="color:#C00000">}</span>, <span style="color:#C00000">{</span> $age <span style="color:#C00000">}`</span>
 +
</code></p>
 +
 +
… is equivalent to …
 +
 +
<p><code>"Name: " || $name || ", " || $age</code></p>
 +
 +
… or …
 +
 +
<p><code>``[Name: `{ $name }`, `{ $age }`]``</code></p>
 +
 +
=Union node tests=
 +
 +
<p><code>/xml/child::<span style="color:#C00000">(a|b)</span></code></p>
 +
 +
<p><code>/xml/element::<span style="color:#C00000">(c|d)</span></code></p>
 +
 +
=Compact lookup syntax=
 +
 +
<p style="white-space: pre-wrap;padding: 1em; border: 1px solid #eaecf0; background-color: #f8f9fa; color: #000; font-family: monospace;">$address<span style="color:#C00000">?$name</span>,
 +
$city<span style="color:#C00000">?"city code"</span>
 +
</p>
 +
 +
… is equivalent to …
 +
 +
<p style="white-space: pre-wrap;padding: 1em; border: 1px solid #eaecf0; background-color: #f8f9fa; color: #000; font-family: monospace;">$address?($name),
 +
$city?("city code")
 +
</p>
  
 
=Maps=
 
=Maps=
  
−
20 new map functions have been added in [https://qt4cg.org/specifications/xpath-functions-40/Overview.html#maps XPath and XQuery Functions and Operators 4.0], namely
+
6 new map functions have been added in [https://qt4cg.org/specifications/xpath-functions-40/Overview.html#maps XPath and XQuery Functions and Operators 4.0], namely
  
 
<ul>
 
<ul>
−
<li><code>fn:atomic-equal</code></li>
 
 
<li><code>map:build</code></li>
 
<li><code>map:build</code></li>
−
<li><code>map:contains</code></li>
 
−
<li><code>map:entries</code></li>
 
−
<li><code>map:entry</code></li>
 
 
<li><code>map:filter</code></li>
 
<li><code>map:filter</code></li>
−
<li><code>map:find</code></li>
 
−
<li><code>map:for-each</code></li>
 
−
<li><code>map:get</code></li>
 
−
<li><code>map:keys</code></li>
 
−
<li><code>map:merge</code></li>
 
 
<li><code>map:of-pairs</code></li>
 
<li><code>map:of-pairs</code></li>
 
<li><code>map:pair</code></li>
 
<li><code>map:pair</code></li>
−
<li><code>map:pairs</code></li>
 
−
<li><code>map:put</code></li>
 
−
<li><code>map:remove</code></li>
 
 
<li><code>map:replace</code></li>
 
<li><code>map:replace</code></li>
−
<li><code>map:size</code></li>
 
 
<li><code>map:substitute</code></li>
 
<li><code>map:substitute</code></li>
−
<li><code>map:values</code></li>
 
 
</ul>
 
</ul>
  
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=Arrays=
 
=Arrays=
  
−
30 new array functions have been added in [https://qt4cg.org/specifications/xpath-functions-40/Overview.html#array XPath and XQuery Functions and Operators 4.0], namely
+
8 new array functions have been added in [https://qt4cg.org/specifications/xpath-functions-40/Overview.html#array XPath and XQuery Functions and Operators 4.0], namely
 +
 
 +
* [[Array_Module#array:build|{{Code|array:build}}]]
 +
* [[Array_Module#array:foot|{{Code|array:foot}}]]
 +
* <code>array:members</code>
 +
* <code>array:of-members</code>
 +
* <code>array:replace</code>
 +
* <code>array:slice</code>
 +
* <code>array:split</code>
 +
* <code>array:trunk</code></li>
 +
 
 +
1 array function has been updated:
  
 
<ul>
 
<ul>
−
<li><code>array:append</code></li>
+
<li><li><code>array:subarray</code></li></li>
−
<li><code>array:build</code></li>
 
−
<li><code>array:empty</code></li>
 
−
<li><code>array:exists</code></li>
 
−
<li><code>array:filter</code></li>
 
−
<li><code>array:flatten</code></li>
 
−
<li><code>array:fold-left</code></li>
 
−
<li><code>array:fold-right</code></li>
 
−
<li><code>array:foot</code></li>
 
−
<li><code>array:for-each</code></li>
 
−
<li><code>array:for-each-pair</code></li>
 
−
<li><code>array:get</code></li>
 
−
<li><code>array:head</code></li>
 
−
<li><code>array:index-where</code></li>
 
−
<li><code>array:insert-before</code></li>
 
−
<li><code>array:join</code></li>
 
−
<li><code>array:members</code></li>
 
−
<li><code>array:of-members</code></li>
 
−
<li><code>array:put</code></li>
 
−
<li><code>array:remove</code></li>
 
−
<li><code>array:replace</code></li>
 
−
<li><code>array:reverse</code></li>
 
−
<li><code>array:size</code></li>
 
−
<li><code>array:slice</code></li>
 
−
<li><code>array:sort</code></li>
 
−
<li><code>array:split</code></li>
 
−
<li><code>array:subarray</code></li>
 
−
<li><code>array:tail</code></li>
 
−
<li><code>array:trunk</code></li>
 
−
<li><code>array:values</code></li>
 
 
</ul>
 
</ul>
  
Line 133: Line 151:
 
;Version 11.0
 
;Version 11.0
  
−
* Added {{Code|otherwise}} operator
+
* Added operator {{Code|otherwise}}  
 +
* Added function <code>map:build</code>
 +
* Added function <code>map:filter</code>
 +
* Added function <code>map:of-pairs</code>
 +
* Added function <code>map:pair</code>
 +
* Added function <code>map:replace</code>
 +
* Added function <code>map:substitute</code>
 +
* Added function [[Array_Module#array:build|{{Code|array:build}}]]
 +
* Added function [[Array_Module#array:foot|{{Code|array:foot}}]]
 +
* Added function <code>array:members</code>
 +
* Added function <code>array:of-members</code>
 +
* Added function <code>array:replace</code>
 +
* Added function <code>array:slice</code>
 +
* Added function <code>array:split</code>
 +
* Added function <code>array:trunk</code>

Latest revision as of 15:35, 16 November 2023

Otherwise operator[edit]

$a otherwise $b

… is equivalent to …

if(exists($a)) then $a else $b

Braced if, optional else[edit]

if($a) { $b } else { $c }

if($a) { if($b) { $c } }

Arrow map operator[edit]

"The cat sat on the mat" => tokenize() =!> concat(".") =!> upper-case() => string-join(" ")

Numeric literals[edit]

1_048_576

0xFC00

0b111000

Abbreviated function syntax[edit]

let $inc := fn($n) { $n + 1 } return $inc(99)

… is equivalent to …

let $inc := function($n) { $n + 1 } return $inc(99)

Focus functions (arity-one)[edit]

let $inc := fn { . + 1 } return $inc(99)

fn:filter($integers, fn { . > 5 })

fn:iterate-while($number, fn { . < 100 }, fn { . * . })

Optional arguments[edit]

declare function strings:get( $value, $default := "EMPTY" ) { $value otherwise $default } strings:get('john')

Keyword arguments[edit]

declare function coordinates( $x := 0, $y := 0 ) { map { "x" : $x, "y" : $y } } coordinates(y := 123)

String templates[edit]

`Name: { $name }, { $age }`

… is equivalent to …

"Name: " || $name || ", " || $age

… or …

``[Name: `{ $name }`, `{ $age }`]``

Union node tests[edit]

/xml/child::(a|b)

/xml/element::(c|d)

Compact lookup syntax[edit]

$address?$name, $city?"city code"

… is equivalent to …

$address?($name), $city?("city code")

Maps[edit]

6 new map functions have been added in XPath and XQuery Functions and Operators 4.0, namely

  • map:build
  • map:filter
  • map:of-pairs
  • map:pair
  • map:replace
  • map:substitute

Map functions are described in Map Module.

Arrays[edit]

8 new array functions have been added in XPath and XQuery Functions and Operators 4.0, namely

1 array function has been updated:

  • array:subarray

Array functions are described in Array Module.

Changelog[edit]

Version 11.0
  • Added operator otherwise
  • Added function map:build
  • Added function map:filter
  • Added function map:of-pairs
  • Added function map:pair
  • Added function map:replace
  • Added function map:substitute
  • Added function array:build
  • Added function array:foot
  • Added function array:members
  • Added function array:of-members
  • Added function array:replace
  • Added function array:slice
  • Added function array:split
  • Added function array:trunk
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