Inspection Module

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This XQuery Module contains functions for extracting internal information about modules and functions and generating documentation.

Conventions

All functions 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. All errors are assigned to the http://basex.org/errors namespace, which is statically bound to the bxerr prefix.

Reflection

inspect:functions

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 addressed file will be compiled, its functions will be added to the query context and returned to the user.
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()

Documentation

inspect:function

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">
  <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">
  <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

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

Signatures inspect:module($input as xs:string) as element(module)
Summary Retrieves the resource addressed by the specified $input, parses it as XQuery module, and generates an element that describes the module's structure.
Errors FODC0002: the addressed resource cannot be retrieved.
Examples An example is shown below.

inspect:xqdoc

Signatures inspect:xqdoc($input as xs:string) as element(xqdoc:xqdoc)
Summary Retrieves the resource addressed by the specified $input, parses it as XQuery module, and generates an xqDoc element.
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 the current status 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.
Errors FODC0002: the addressed resource cannot be retrieved.
Examples An example is shown below.

Examples

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">
    <description>This is a sample string.</description>
  </variable>
  <function name="samples:same" uri="http://basex.org/modules/samples">
    <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>

Changelog

Version 7.9

This module was introduced with Version 7.7.