anchor.diff:  %% use eunit
   -include_lib("eunit/include/eunit.hrl").
   
  -%% export all
  --compile(export_all).
  -
  -%% eunit test; we need a longer timeout because some of it is rather slow...
  -triq_test_() ->
  -    {timeout, 60,
  -     fun() ->
  -             true = triq:module(?MODULE)
  -     end}.
   
   boolean_test() ->
       Unique = fun ordsets:from_list/1,
  
positive.code:                                       )
                       end, lists:seq(1,100)).
  
  list_shrink2_testx() ->
      %% test that a list doesn't easily end in a local 'smallest counterexample'
      true = lists:all(fun(_) ->
                               [[]] = triq:counterexample(
                                         ?FORALL(L, list(oneof([a,b])),
                                                 not is_pairs_list(L))
                                        ),
                               true
                       end, lists:seq(1,100)).
  
  is_pairs_list([])      -> true;
  is_pairs_list([X,X|T]) -> is_pairs_list(T);
  is_pairs_list(_)       -> false.
  
  oneof_test() ->
      [{X,Y}] = triq:counterexample(
  
negative.code: counterexample_test() ->
      Counterexample = triq:counterexample(xprop_delete()),
      ?assertEqual(false, triq:check(xprop_delete(), Counterexample)).
  
  
  %% -------------------------------------------------------------------
  %% Property Testing
  %% -------------------------------------------------------------------
  
  run_property_testing_test_() ->
      {timeout, 60, fun run_property_testing_case/0}.
  
  run_property_testing_case() ->
      EunitLeader = erlang:group_leader(),
      erlang:group_leader(whereis(user), self()),
      Res = triq:module(?MODULE),
      erlang:group_leader(EunitLeader, self()),
      ?assert(Res).
  