anchor.diff:  
   %% @doc Returns the group names which have at least 1 process running on `Node' for the `default' scope.
   %%
  -%% Same as calling `group_names(default, node())', see {@link group_names/2}.
  +%% @equiv group_names(default, node())
  +%% @end
   -spec local_group_names() -> [GroupName :: term()].
   local_group_names() ->
       syn_groups:local_group_names().
   
   %% @doc Returns the group names which have at least 1 process running on `Node' for the specified `Scope'.
   %%
  -%% Same as calling `group_names(Scope, node())', see {@link group_names/2}.
  +%% @equiv group_names(Scope, node())
  +%% @end
   -spec local_group_names(Scope :: atom()) -> [GroupName :: term()].
   local_group_names(Scope) ->
       syn_groups:local_group_names(Scope).
   
   %% @doc Publish a message to all group members in the `default' scope.
   %%
  -%% Same as calling `publish(default, GroupName, Message)', see {@link publish/3}.
  +%% @equiv publish(default, GroupName, Message)
  +%% @end
   %%
   %% <h2>Examples</h2>
   %% <h3>Elixir</h3>
  
positive.code: 
  %% @doc Returns whether a `pid()' is a member of GroupName in the `default' scope.
  %%
  %% Same as calling `is_member(default, GroupName, Pid)', see {@link is_member/3}.
  -spec is_member(GroupName :: any(), Pid :: pid()) -> boolean().
  is_member(GroupName, Pid) ->
      syn_groups:is_member(GroupName, Pid).
  
negative.code: 
  %% @doc Registers a process with metadata in the `default' scope OR with undefined metadata in the specified `Scope'.
  %%
  %% Equivalent to`register(default, Name, Pid, Meta)' or `register(Scope, Name, Pid, undefined)'
  %% depending on the position of the `pid()' value. See {@link register/4} for more info.
  -spec register(NameOrScope :: any(), PidOrName :: any(), MetaOrPid :: any()) -> ok | {error, Reason :: any()}.
  register(NameOrScope, PidOrName, MetaOrPid) ->
  