Hi Andreas, 

I think you are calling the inspect function function on the following HTML Page: 
https://www.w3.org/2005/xpath-functions/
Per documentation, the function does the following:
If a $uri is specified, the addressed module will be compiled, and its functions will be added to the query context and returned to the user

As the URI contains no XQuery module, the function will error.

Currently inspect:functions only works on user-defined modules.



Hope this helps!

Michael 

Am 06.05.2019 um 02:47 schrieb Andreas Mixich <mixich.andreas@gmail.com>:

Hi,

opening a new sheet in the GUI I just executed:


and this is what I got:

Error:
[XPST0003] Processing instruction has illegal name: xml.

Optimized Query:

The Query itself is, as returned by BaseX, interestingly, an XHTML file, which seems to have been produced via Saxon, here are the first lines:

<?xml version="1.0" encoding="UTF-8"?>
<!--XSLT Processor: Saxonica SAXON HE 9.6.0.7-->
<html xmlns="http://www.w3.org/1999/xhtml" lang="EN">
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
    <title>XQuery, XPath, and XSLT Functions and Operators Namespace Document </title>
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"/>
    <style type="text/css"> </style>
    <link rel="stylesheet" type="text/css" href="http://www.w3.org/StyleSheets/TR/base.css"/>
  </head>
  <body>
    <div class="head">
      <p>
        <a href="http://www.w3.org/">
          <img src="http://www.w3.org/Icons/w3c_home" alt="W3C" height="48" width="72"/>
        </a>
      </p>
      <h1><a name="title" id="title"/>XQuery, XPath, and XSLT Functions and Operators Namespace Document </h1>
      <h2>21 March 2017</h2>
    </div>
    <nav id="toc">
      <h2><a id="contents"/>Table of Contents </h2>
      <ol class="toc">
        <li>
          <a href="#intro">
            <span class="secno">1 </span>
            <span class="content">Introduction</span>
          </a>
          <ol class="toc"/>
        </li>


And here is the QueryPlan:

Query Plan:
<QueryPlan compiled="true" updating="false">
  <InspectFunctions name="inspect:functions" type="(function(*))*">
    <Str type="xs:string" size="1">http://www.w3.org/2005/xpath-functions</Str>
  </InspectFunctions>
</QueryPlan>

--
Minden jót, all the best, Alles Gute,
Andreas Mixich