anchor.diff:  %% and false when it hasn't, in which case a 500 error is sent.
   process_post(Req, State) ->
   	case call(Req, State, process_post) of
  +		{halt, Req2, HandlerState} ->
  +			terminate(Req2, State#state{handler_state=HandlerState});
   		{true, Req2, HandlerState} ->
   			State2 = State#state{handler_state=HandlerState},
   			next(Req2, State2, 201);
  
positive.code: 			respond(Req3, State#state{handler_state=HandlerState}, 307);
  		{false, Req2, HandlerState} ->
  			is_post_to_missing_resource(Req2, State#state{handler_state=HandlerState}, 410);
  		no_call ->
  			is_post_to_missing_resource(Req, State, 410)
  	end.
  
negative.code: 	case call(Req, State, content_types_provided) of
  		no_call ->
  			not_acceptable(Req, State);
  		{halt, Req2, HandlerState} ->
  			terminate(Req2, State#state{handler_state=HandlerState});
  		{[], Req2, HandlerState} ->
  			not_acceptable(Req2, State#state{handler_state=HandlerState});
  		{CTP, Req2, HandlerState} ->
  