XPathException e = new XPathException("Circular definition of parameter " +
getVariableQName().getDisplayName());
e.setXPathContext(context);
e.setErrorCode(isXSLT() ? "XTDE0640" : "XQST0054");
// Detect it more quickly the next time (in a pattern, the error is recoverable)
select = new ErrorExpression(e);
throw e;
} else {
throw err;
}
}