anchor.diff:  
     case Matches of
       [{Name,Arity}|_] ->
  -      Key = ets:lookup_element(Table, {Name, Arity }, 2),
  -      Tuple = { import_conflict, { Key, Name, Arity } },
  +      Key = ets:lookup_element(Table, { Name, Arity }, 2),
  +      Tuple = { import_conflict, { hd(Key), Name, Arity } },
         elixir_errors:form_error(Meta, File, ?MODULE, Tuple);
       [] ->
         ok
  
positive.code: 
  %% Macros implemented in Erlang that are not overridable.
  
  non_overridable_macros() ->
    [
      {'^',1},
      {'=',2},
  
negative.code: %% Ensure the given functions don't clash with any
  %% of Elixir non overridable macros.
  
  ensure_no_special_form_conflict(Meta, File, Key, [{Name,Arity}|T], Reason) ->
    Values = lists:filter(fun({X,Y}) ->
      (Name == X) andalso ((Y == '*') orelse (Y == Arity))
    end, special_form()),
  
    case Values /= [] of
      true  ->
        Tuple = { Reason, { Key, Name, Arity } },
        elixir_errors:form_error(Meta, File, ?MODULE, Tuple);
      false -> ensure_no_special_form_conflict(Meta, File, Key, T, Reason)
    end;
  
  ensure_no_special_form_conflict(_Meta, _File, _Key, [], _) -> ok.
  
  %% ERROR HANDLING
  
  