message: Give up trying to use macro on BlendedFilter,
  Current code is the best one I can write for now... keep it for the future.
diff: @@ -59,17 +59,13 @@ impl<'a, T: 'static + Debug> BlendedFilter<'a, T> {
  let c = self.filter.context;
  let b0 = self.context;
  - // TODO: Ready to use macro, seriously?
  - let c0;
  - let c1;
  - let c2;
  - let c3;
  - let c4;
  - let c5;
  - let c6;
  - let c7;
  - let c8;
  - let c9;
  + /* TODO:
  + * Borrow BlendContext and convert it into FilterContext.
  + * This is the best I can do for now...
  + * Max number of tables can be joined in a single depth is 10.
  + */
  + let c0; let c1; let c2; let c3; let c4;
  + let c5; let c6; let c7; let c8; let c9;
  c0 = match &b0.next { Some(b1) => {
  c1 = match &b1.next { Some(b2) => {
  