anchor.diff:  let with_captured_errors' env f =
     let tcenv = snd env in
     try
  -    f ()
  +    f env
     with
     | Failure (msg) ->
       let msg = "ASSERTION FAILURE: " ^ msg ^ "\n" ^
  
positive.code: 
    let env, finish_name_tracking = track_name_changes env in // begin name tracking…
  
    match with_captured_errors env
            (fun () -> Some (tc_prims_and_deps env st.prepl_fname)) with
    | Some (deps, repl_deps, env) ->
      on_successful_init (finish_name_tracking env) deps repl_deps
    | None ->
      // CPC This should pop until the dependency checker's stack is empty
      on_failed_init (finish_name_tracking env)
  
  let run_push (st: repl_state) query =
  
negative.code:   // if this is the first chunk, we need to restore the command line options.
    let restore_cmd_line_options, (env, deps) =
      if repl_stack_empty ()
      then true, (env, st.repl_deps) // FIXME: update_deps st.repl_fname env st.repl_deps
      else false, (env, st.repl_deps) in
  
    if restore_cmd_line_options then
  