I have am XML file with XSL to process it.
That works fine using an input element like <input pattern="^[^ ].*[^ ]$">.
However when I changed it to <input pattern="^[^ ]{2,}.*[^ ]$">, Firefox ESR 115.3.1 complained:
Fehler beim Laden des Stylesheets: XPath-Verarbeitungsfehler: Binärer Operator erwartet:
(In English (most likely): "Error loading stylesheets: XPath processing error: Binary Operator expected:")
I completely fail to understand how to debug this, what triggers the error, and how to fix it (when I added backslashed before { and }I got a different error message, saying "Invalid character found:").
What makes things harder to understand is that any details (like line, token) are absent in the error message, and when I try to display the source, I only get an empty window.
<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="#default"?>
<xsl:stylesheet id="default" version="1.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:test="test"
exclude-result-prefixes="xsl test">
<test:XML>
<order>
</order>
</test:XML>
<xsl:output method="html" encoding="UTF-8" indent="yes"/>
<xsl:template match="/xsl:stylesheet">
<xsl:apply-templates />
</xsl:template>
<xsl:template match="xsl:*" /><!-- ignore -->
<xsl:template match="test:XML/order">
<html xmlns="http://www.w3.org/1999/xhtml">
<body>
<form>
<input id="customer-name" type="text" name="i.user.name"
size="25" maxlength="40" placeholder="Name"
pattern="^[^ ]{2,}.*[^ ]$" required="required" />
</form>
</body>
</html>
</xsl:template>
</xsl:stylesheet>
XSLT uses curly brackets { and } in attribute values as so called attribute value templates to delimit embedded XPath expressions. So in XSLT, in such attributes, if you want a literal { or }, you need to double them as e.g. {{ and }}, e.g. pattern="^[^ ]{{2,}}.*[^ ]$".