anchor.diff:                  {ok, AlreadyThere} when AlreadyThere =:= Page ->
                       %% Alright, well, let's go continue the repair/writing,
                       %% since we agree on the page's value.
  -                    append_single_page_to_chain(Rest, Epoch, LPN, Page, Nth+1);
  +                    write_single_page_to_chain(Rest, Epoch, LPN, Page, Nth+1);
                   error_badepoch ->
                       %% TODO: same TODO as the above error_badepoch case.
                       error_badepoch;
  
positive.code:                                    PageSize, NumPages * (PageSize * ?PAGE_OVERHEAD)))
       end || X <- lists:seq(1, NumFLUs)].
  
  append_test() ->
      NumFLUs = 4,
      PageSize = 8,
      NumPages = 10,
      FLUs = [F1, F2, F3, F4] = setup_basic_flus(NumFLUs, PageSize, NumPages),
      {ok, Seq} = corfurl_sequencer:start_link(FLUs),
  
      try
          P1 = new_simple_projection(1, 1, 1*100, [[F1, F2], [F3, F4]]),
          [begin
               Pg = lists:flatten(io_lib:format("~8..0w", [X])),
               ok = append_page(Seq, P1, list_to_binary(Pg))
           end || X <- lists:seq(1, 5)],
  
          ok
      after
          corfurl_sequencer:stop(Seq),
  
negative.code:             %% else junked us.
              %% TODO We should go trim our previously successful writes?
              error_trimmed;
          error_overwritten when Nth == 1 ->
              %% The sequencer lied, or we didn't use the sequencer and
              %% guessed and guessed poorly, or someone is accidentally
              %% trying to take our page.  Shouganai, these things happen.
              error_overwritten;
          error_overwritten when Nth > 1 ->
              %% The likely cause is that another reader has noticed that
              %% we haven't finished writing this page in this chain and
              %% has repaired the remainder of the chain while we were
  