//Expression eval = new Atomizer(new ContextItemExpression(), config);
StringFn sf = (StringFn)SystemFunction.makeSystemFunction(
"string", new Expression[]{new ContextItemExpression()});
StringLiteral regex = new StringLiteral("\\s+");
Tokenize use = (Tokenize)SystemFunction.makeSystemFunction("tokenize", new Expression[]{sf, regex});
KeyDefinition key = new KeyDefinition(idref, use, null, null);
key.setIndexedItemType(BuiltInAtomicType.STRING);
try {
addKeyDefinition(StandardNames.getStructuredQName(StandardNames.XS_IDREFS), key, config);
} catch (XPathException err) {