anchor.diff:      end;
   check_app_hooks(_, []) -> hooks_ok.
   
  +-spec extract_hooks([any()]) -> [hook()].
   extract_hooks(CheckedPlugins) ->
       extract_hooks(CheckedPlugins, []).
   
  
positive.code:                    atom(),
                     atom(),
                     non_neg_integer()}.
  
  %%%===================================================================
  %%% API
  
negative.code:      [{tuple, 1, [{atom, 1, error}, {atom, 1, no_matching_hook_found}]}]
      }.
  
  all_clauses(I, [#hook{name = Name, arity = Arity} = Hook |Rest], Acc, Info) ->
      Hooks = [H || #hook{name = N, arity = A} = H <- Rest,
                    (N == Name) and (A == Arity)],
      Clause =
      clause(I, Name, Arity,
  