@Override
        public void visitXmlAttribute(@NotNull XmlAttribute attribute) {
            if (!XsltSupport.isVariableOrParamName(attribute)) {
                return;
            }

            final XmlTag tag = attribute.getParent();
            if (XsltSupport.isTopLevelElement(tag)) {
                return;
            }
            final XsltVariable variable = XsltElementFactory.getInstance().wrapElement(tag, XsltVariable.class);
            final String name = variable.getName();
            if (name == null || name.length() == 0) {
                return;
            }

            XsltValidator.checkUnusedVariable(variable, myHolder);
        }
@Override
        public void visitXmlAttribute(@NotNull XmlAttribute attribute)