/** Simplify: add a third implicit argument, the context document */
public Expression simplify(StaticContext env) throws XPathException {
if (!internal && !(env instanceof ExpressionContext)) {
throw new StaticError(
"The key() function is available only in XPath expressions within an XSLT stylesheet");
}
KeyFn f = (KeyFn) super.simplify(env);
if (argument.length == 2) {
f.addContextDocumentArgument(2, "key");
}
return f;
}
/** Non-standard constructor to create an internal call on key() with a known key fingerprint */
public static KeyFn internalKeyCall(
NamePool pool, int fingerprint, String name, Expression value, Expression doc) {
KeyFn k = new KeyFn();
Expression[] arguments = {new StringValue(name), value, doc};
k.argument = arguments;
k.keyFingerprint = fingerprint;
k.checked = true;
k.internal = true;
k.setDetails(StandardFunction.getFunction("key", 3));
k.setFunctionNameCode(pool.allocate("fn", NamespaceConstant.FN, "key"));
k.adoptChildExpression(value);
k.adoptChildExpression(doc);
return k;
}