// We create a method key to uniquely identify this function so that we
// can cache the object needed to invoke it. This way, we only pay the
// reflection overhead on the first call.
Function extension = new FuncExtFunction(ns, funcName, String.valueOf(getNextMethodId()));
try
{
int i = 0;
while (opPos < endExtFunc)
{
int nextOpPos = getNextOpPos(opPos);
extension.setArg(this.compile(opPos), i);
opPos = nextOpPos;
i++;
}