anchor.diff:    end.
   
   %% @doc Call specified function with arguments and environment.
  -%%
  -%% @spec step_call_function({atom(), atom()} | fun(),
  -%%                          [xmerlrpc_xml:proc_arg()],
  -%%                          list()) ->
  -%%     {ok, xmerlrpc_xml:proc_arg()}
  -%%   | {exception, Exception :: iolist()}
  +
  +-spec step_call_function(proc_spec(), [xmerlrpc_xml:proc_arg()],
  +                         call_environment()) ->
  +    {ok, xmerlrpc_xml:proc_arg()}
  +  | {exception, Exception :: iolist()}.
  +% | {error, term()}.
   
   step_call_function(Function, Args, Environment) ->
     % {ok,_} | {error,_} are for case when error is signaled by returned value
  
positive.code: 
  %%%---------------------------------------------------------------------------
  
  %% @type proc_spec() = {Module :: atom(), Function :: atom()} | fun().
  
  %% @type http_response() =
  %%   {StatusCode :: integer(), Headers :: list(), Body :: iolist()}.
  
  %%%---------------------------------------------------------------------------
  
  
negative.code:   end.
  
  %% @doc Execute RPC request.
  
  -spec step_execute_request(xmerlrpc_xml:proc_name(), [xmerlrpc_xml:proc_arg()],
                             call_environment(), dispatch_table()) ->
    http_response().
  
  step_execute_request(ProcName, ProcArgs, Environment, DispatchTable) ->
    case step_dispatch(ProcName, ProcArgs, Environment, DispatchTable) of
  