Inspection Module

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Conventions[edit]

All functions and errors in this module are assigned to the http://basex.org/modules/inspect namespace, which is statically bound to the inspect prefix.
xqDoc document instances are assigned to the http://www.xqdoc.org/1.0 namespace, which is statically bound to the xqdoc prefix.

Reflection[edit]

inspect:functions[edit]

Signatures inspect:functions() as function(*)*
inspect:functions($uri as xs:string) as function(*)*
Summary Returns function items for all user-defined functions (both public and private) that are known in the current query context. If a $uri is specified, the specified resource will be retrieved as string and compiled, and its functions will be added to the query context and returned to the user. A relative URI will be resolved against the static base URI of the query.
Examples Invokes the declared functions and returns their values:
declare %private function local:one() { 12 };
declare %private function local:two() { 34 };
for $f in inspect:functions() return $f()

Compiles all functions in code.xqm and invokes the function named run:

let $uri := 'code.xqm'
let $name := 'run'
for $f in inspect:functions($uri)
where local-name-from-QName(function-name($f)) = $name
return $f()
Errors parse: Error while parsing a module.

inspect:function-annotations[edit]

Signatures inspect: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:
inspect: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' };
inspect:function-annotations(local:f#0)

inspect:static-context[edit]

Signatures inspect:static-context($function as function(*)?, $name as xs:string) as item()*
Summary Returns a component of the static context of a $function with the specified $name. If no function is supplied, the current static context is considered.
The following components can be requested:
  • base-uri: Static base URI.
  • namespaces: Prefix/URI map with all statically known namespaces.
  • element-namespace: Default element/type namespace URI, or an empty sequence if it is absent.
  • function-namespace: Default function namespace URI, or an empty sequence if it is absent.
  • collation: URI of the default collation.
  • ordering: Ordering mode (ordered/unordered)
  • construction: Construction mode (preserve/strip)
  • default-order-empty: Default order for empty sequences (greatest/least)
  • boundary-space: Boundary-space policy (preserve/strip)
  • copy-namespaces: Copy-namespaces mode (inherit/no-inherit, preserve/no-preserve)
  • decimal-formats: Nested map with all statically known decimal formats
Examples
  • Returns the static base URI (same as static-base-uri()):
inspect:static-context((), 'base-uri')
  • Returns a map with all namespaces that are statically known in the module of the specified function:
import module namespace data = 'data.xqm';
inspect:static-context(data:get#1, 'namespaces')
Errors unknown: The specified component does not exist.

Documentation[edit]

inspect:type[edit]

Signatures inspect:type($value as item()*) as xs:string
inspect:type($value as item()*, $options as map(*)) as xs:string
Summary Returns a string representation of the type of a $value:
  • The string includes the occurrence indicator.
  • The type of functions and nodes may be stricter than the returned type.
  • For type checking, the standard expressions typeswitch and instance of should be used instead.

The following $options are available:

  • item: If enabled, only the item type is returned and the occurrence indicator is omitted. The default is false().
  • mode: If value is specified, the assigned type of the result value is returned. With expression the type of the input expression is returned (please note that the original expression may already have been rewritten at compile-time). With computed, the exact value is computed at runtime, based on the expression and the result value. The default is computed.
Examples
  • inspect:type((<a/>, <a/>)) yields element(a)+
  • inspect:type(map { 'a': (1, 2)[. = 1] }) yields map(xs:string, xs:integer)
  • inspect:type(1 to 100, map { 'item': true() }) yields xs:integer

inspect:function[edit]

Signatures inspect:function($function as function(*)) as element(function)
Summary Inspects the specified $function and returns an element that describes its structure. The output of this function is similar to eXist-db’s inspect:inspect-function function.
Examples The query inspect:function(count#1) yields:
<function name="count" uri="http://www.w3.org/2005/xpath-functions" external="false">
  <argument type="item()" occurrence="*"/>
  <return type="xs:integer"/>
</function>

The function…

(:~
 : This function simply returns the specified integer.
 : @param $number  number to return
 : @return         specified number
 :)
declare %private function local:same($number as xs:integer) as xs:integer {
  $number
};

…is represented by inspect:function(local:same#1) as…

<function name="local:same" uri="http://www.w3.org/2005/xquery-local-functions" external="false">
  <argument type="xs:integer" name="number">number to return</argument>
  <annotation name="private" uri="http://www.w3.org/2012/xquery"/>
  <description>This function simply returns the specified integer.</description>
  <return type="xs:integer">specified number</return>
</function>

inspect:context[edit]

Signatures inspect:context() as element(context)
Summary Generates an element that describes all variables and functions in the current query context.
Examples Evaluate all user-defined functions with zero arguments in the query context:
inspect:context()/function ! function-lookup(QName(@uri, @name), 0) ! .()

Return the names of all private functions in the current context:

for $f in inspect:context()/function
where $f/annotation/@name = 'private'
return $f/@name/string()

inspect:module[edit]

Signatures inspect:module($uri as xs:string) as element(module)
Summary Retrieves the resource located at the specified $uri, parses it as XQuery module, and generates an element that describes the module's structure. A relative URI will be resolved against the static base URI of the query.
Examples An example is shown below.
Errors parse: Error while parsing a module.

inspect:xqdoc[edit]

Signatures inspect:xqdoc($uri as xs:string) as element(xqdoc:xqdoc)
Summary Retrieves the resource located at the specified $uri, parses it as XQuery module, and generates an xqDoc element. A relative URI will be resolved against the static base URI of the query.
xqDoc provides a simple vendor-neutral solution for generating documentation from XQuery modules. The documentation conventions have been inspired by the JavaDoc standard. Documentation comments begin with (:~ and end with :), and tags start with @. xqDoc comments can be specified for main and library modules and variable and function declarations.

We have slightly extended the xqDoc conventions to do justice to more recent versions of XQuery (Schema: xqdoc-1.1.30052013.xsd):

  • an <xqdoc:annotations/> node is added to each variable or function that uses annotations. The xqdoc:annotation child nodes may have additional xqdoc:literal elements with type attributes (xs:string, xs:integer, xs:decimal, xs:double) and values.
  • a single <xqdoc:namespaces/> node is added to the root element, which summarizes all prefixes and namespace URIs used or declared in the module.
  • name and type elements are added to variables.
Examples An example is shown below.
Errors parse: Error while parsing a module.

Examples[edit]

This is the sample.xqm library module:

(:~ 
 : This module provides some sample functions to demonstrate
 : the features of the Inspection Module.
 :
 : @author   BaseX Team
 : @see      http://docs.basex.org/wiki/XQDoc_Module
 : @version  1.0
 :)
module namespace samples = 'http://basex.org/modules/samples';

(:~ This is a sample string. :)
declare variable $samples:test-string as xs:string := 'this is a string';

(:~
 : This function simply returns the specified integer.
 : @param   $number number to return
 : @return  specified number
 :)
declare %private function samples:same($number as xs:integer) as xs:integer {
  $number
};

If inspect:module('sample.xqm') is run, the following output will be generated:

<module prefix="samples" uri="http://basex.org/modules/samples">
  <description>This module provides some sample functions to demonstrate
the features of the Inspection Module.</description>
  <author>BaseX Team</author>
  <see>http://docs.basex.org/wiki/XQDoc_Module</see>
  <version>1.0</version>
  <variable name="samples:test-string" uri="http://basex.org/modules/samples" type="xs:string" external="false">
    <description>This is a sample string.</description>
  </variable>
  <function name="samples:same" uri="http://basex.org/modules/samples" external="false">
    <argument name="number" type="xs:integer">number to return</argument>
    <annotation name="private" uri="http://www.w3.org/2012/xquery"/>
    <description>This function simply returns the specified integer.</description>
    <return type="xs:integer">specified number</return>
  </function>
</module>

The output looks as follows if inspect:xqdoc('sample.xqm') is called:

<xqdoc:xqdoc xmlns:xqdoc="http://www.xqdoc.org/1.0">
  <xqdoc:control>
    <xqdoc:date>2013-06-01T16:59:33.654+02:00</xqdoc:date>
    <xqdoc:version>1.1</xqdoc:version>
  </xqdoc:control>
  <xqdoc:module type="library">
    <xqdoc:uri>http://basex.org/modules/samples</xqdoc:uri>
    <xqdoc:name>sample.xqm</xqdoc:name>
    <xqdoc:comment>
      <xqdoc:description>This module provides some sample functions to demonstrate
the features of the Inspection Module.</xqdoc:description>
      <xqdoc:author>BaseX Team</xqdoc:author>
      <xqdoc:see>http://docs.basex.org/wiki/XQDoc_Module</xqdoc:see>
      <xqdoc:version>1.0</xqdoc:version>
    </xqdoc:comment>
  </xqdoc:module>
  <xqdoc:namespaces>
    <xqdoc:namespace prefix="samples" uri="http://basex.org/modules/samples"/>
  </xqdoc:namespaces>
  <xqdoc:imports/>
  <xqdoc:variables>
    <xqdoc:variable>
      <xqdoc:name>samples:test-string</xqdoc:name>
      <xqdoc:comment>
        <xqdoc:description>This is a sample string.</xqdoc:description>
      </xqdoc:comment>
      <xqdoc:type>xs:string</xqdoc:type>
    </xqdoc:variable>
  </xqdoc:variables>
  <xqdoc:functions>
    <xqdoc:function arity="1">
      <xqdoc:comment>
        <xqdoc:description>This function simply returns the specified integer.</xqdoc:description>
        <xqdoc:param>$number number to return</xqdoc:param>
        <xqdoc:return>specified number</xqdoc:return>
      </xqdoc:comment>
      <xqdoc:name>samples:same</xqdoc:name>
      <xqdoc:annotations>
        <xqdoc:annotation name="private"/>
      </xqdoc:annotations>
      <xqdoc:signature>declare %private function samples:same($number as xs:integer) as xs:integer</xqdoc:signature>
      <xqdoc:parameters>
        <xqdoc:parameter>
          <xqdoc:name>number</xqdoc:name>
          <xqdoc:type>xs:integer</xqdoc:type>
        </xqdoc:parameter>
      </xqdoc:parameters>
      <xqdoc:return>
        <xqdoc:type>xs:integer</xqdoc:type>
      </xqdoc:return>
    </xqdoc:function>
  </xqdoc:functions>
</xqdoc:xqdoc>

Errors[edit]

Code Description
parse Error while parsing a module.
unknown The specified component does not exist.

Changelog[edit]

Version 9.6
Version 9.3
Version 8.5
Version 7.9

This module was introduced with Version 7.7.