anchor.diff:              not_found -> erruby_object:find_const(erruby_object:object_class(), Name);
               _ -> LocalConst
             end,
  -  Env#{ret_val => Const};
  +  erruby_rb:return(Const, Env);
   
   
   eval_ast(Ast, Env) ->
  
positive.code: eval_ast({ast, type, lvar, children, [Name]}, Env) ->
    erruby_debug:debug_1("searching lvar ~p~n in frame~p~n", [Name, Env]),
    #{ lvars := #{Name := Val}} = Env,
    Env#{ ret_val => Val};
  
  eval_ast({ast, type, def, children, Children}, Env) ->
    [Name | [ {ast, type, args, children, Args} , Body ] ] = Children,
  
negative.code: 
  pop_frame(Frame) ->
    #{ret_val := RetVal, prev_frame := PrevFrame} = Frame,
    erruby_rb:return(RetVal, PrevFrame).
  
  default_env() ->
    {ok, _ObjectClass} = erruby_object:init_object_class(),
  