// represents the (hopefully structured) source code of a Java(X) expression
// call str() to get JavaX expression
// call quickEval() to try to evaluate right now
//
// A is return type of expression

sinterface ICachedJavaXExpr<A> {
  // override to provide an evaluation result
  public default A quickEval() { fail("Can't quick eval: " + toStringWithClassName(this)); }
}