anchor.diff: -%% @doc This is the Erlang side of the graph database.
  +%% @doc This is the Erlang API of the graph database.
   %% 
   %% @author Ingo Schramm
   
  
positive.code:         Error -> Error
      end.
  
  
  
  
negative.code: vertex_get_edges(V=?VERTEX(Id), Type) ->
      [ E || E=?EDGE(EId,T,A,B) <- vertex_get_edges(V), T =:= Type ].
  
  % @doc Get all vertices connected ith a given vertex.
  vertex_get_neighbourhood(V=?VERTEX(Id)) ->
      get_other_nodes(Id,vertex_get_edges(V)).
  
  % @doc Get all vertices connected with a given vertex
  % by an edge of a given type.
  vertex_get_neighbourhood(V=?VERTEX(Id), Type) ->
      get_other_nodes(Id,vertex_get_edges(V, Type)).
  
  % @doc Set a property at a vertex.
  vertex_set_property(?VERTEX(Id), Key, Val) ->
      private_set_property(vertex, Id, Key, Val).
  
  % @doc Delete a property at a vertex.
  vertex_del_property(?VERTEX(Id), Key) ->
      private_del_property(vertex, Id, Key).
  
  % @doc Get a property at a vertex.
  vertex_get_property(?VERTEX(Id), Key) ->
      private_get_property(vertex, Id, Key).
  
  % @doc Get all properties at a vertex.
  vertex_get_properties(?VERTEX(Id)) ->
      private_get_properties(vertex, Id).
  
  