Skeleton of package body

2 files changed, 1375 insertions, 1 deletions

diff --git a/src/ada-containers-directed_graphs.adb b/src/ada-containers-directed_graphs.adb
new file mode 100644
index 0000000..51728dd
--- /dev/null
+++ b/src/ada-containers-directed_graphs.adb
@@ -0,0 +1,1374 @@
+
+
+package body Ada.Containers.Directed_Graphs is
+
+
+    pragma Warnings (Off, "variable ""Busy*"" is not referenced");
+    pragma Warnings (Off, "variable ""Lock*"" is not referenced");
+    --  See comment in Ada.Containers.Helpers
+
+
+
+
+    ---------
+    -- "=" --
+    ---------
+
+    overriding function "="
+           (Left, Right : in Graph)
+        return Boolean is
+    begin
+        return False;
+    end "=";
+
+
+
+
+    ------------
+    -- Adjust --
+    ------------
+
+    procedure Adjust
+           (Container : in out Graph) is
+    begin
+        null;
+    end Adjust;
+
+
+
+
+    ------------
+    -- Append --
+    ------------
+
+    procedure Append
+           (Container : in out Graph;
+            Position  :    out Cursor) is
+    begin
+        null;
+    end Append;
+
+    procedure Append
+           (Container : in out Graph;
+            Label     : in     Node_Label_Type;
+            Position  :    out Cursor) is
+    begin
+        null;
+    end Append;
+
+
+
+
+    ------------------
+    -- Append_Label --
+    ------------------
+
+    procedure Append_Label
+           (Container : in out Graph;
+            Node      : in     Node_Type;
+            Label     : in     Node_Label_Type) is
+    begin
+        null;
+    end Append_Label;
+
+    procedure Append_Label
+           (Position : in out Cursor;
+            Label    : in     Node_Label_Type) is
+    begin
+        null;
+    end Append_Label;
+
+    procedure Append_Label
+           (Container : in out Graph;
+            Edge      : in     Edge_Type;
+            Label     : in     Edge_Label_Type) is
+    begin
+        null;
+    end Append_Label;
+
+
+
+
+    ------------
+    -- Assign --
+    ------------
+
+    procedure Assign
+           (Target : in out Graph;
+            Source : in     Graph) is
+    begin
+        null;
+    end Assign;
+
+
+
+
+    --------------
+    -- Children --
+    --------------
+
+    function Children
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Children;
+
+    function Children
+           (Position : in Cursor)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Children;
+
+
+
+
+    -----------
+    -- Clear --
+    -----------
+
+    procedure Clear
+           (Container : in out Graph) is
+    begin
+        null;
+    end Clear;
+
+
+
+
+    ------------------
+    -- Clear_Labels --
+    ------------------
+
+    procedure Clear_Labels
+           (Container : in out Graph) is
+    begin
+        null;
+    end Clear_Labels;
+
+
+
+
+    ------------------------------
+    -- Constant_Label_Reference --
+    ------------------------------
+
+    function Constant_Label_Reference
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Node_Label_Constant_Reference is
+    begin
+        return R : Node_Label_Constant_Reference :=
+           (Element => null,
+            Control => (Ada.Finalization.Controlled with null));
+    end Constant_Label_Reference;
+
+    function Constant_Label_Reference
+           (Position : in Cursor)
+        return Node_Label_Constant_Reference is
+    begin
+        return R : Node_Label_Constant_Reference :=
+           (Element => null;
+            Control => (Ada.Finalization.Controlled with null));
+    end Constant_Label_Reference;
+
+    function Constant_Label_Reference
+           (Container : in Graph;
+            Edge      : in Edge_Type)
+        return Edge_Label_Constant_Reference is
+    begin
+        return R : Edge_Label_Constant_Reference :=
+           (Element => null;
+            Control => (Ada.Finalization.Controlled with null));
+    end Constant_Label_Reference;
+
+
+
+
+    --------------
+    -- Contains --
+    --------------
+
+    function Contains
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains;
+
+    function Contains
+           (Container : in Graph;
+            Node      : in Node_Type;
+            Label     : in Node_Label_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains;
+
+    function Contains
+           (Container : in Graph;
+            Edge      : in Edge_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains;
+
+    function Contains
+           (Container : in Graph;
+            Edge      : in Edge_Type;
+            Label     : in Edge_Label_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains;
+
+
+
+
+    --------------------------
+    -- Contains_In_Subgraph --
+    --------------------------
+
+    function Contains_In_Subgraph
+           (Position : in Cursor;
+            Node     : in Node_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains_In_Subgraph;
+
+    function Contains_In_Subgraph
+           (Position : in Cursor;
+            Node     : in Node_Type;
+            Label    : in Node_Label_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains_In_Subgraph;
+
+    function Contains_In_Subgraph
+           (Position : in Cursor;
+            Edge     : in Edge_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains_In_Subgraph;
+
+    function Contains_In_Subgraph
+           (Position : in Cursor;
+            Edge     : in Edge_Type;
+            Label    : in Edge_Label_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains_In_Subgraph;
+
+
+
+
+    --------------------
+    -- Contains_Label --
+    --------------------
+
+    function Contains_Label
+           (Container : in Graph;
+            Label     : in Node_Label_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains_Label;
+
+    function Contains_Label
+           (Container : in Graph;
+            Label     : in Edge_Label_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains_Label;
+
+
+
+
+    --------------------------------
+    -- Contains_Label_In_Subgraph --
+    --------------------------------
+
+    function Contains_Label_In_Subgraph
+           (Position : in Cursor;
+            Label    : in Node_Label_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains_Label_In_Subgraph;
+
+    function Contains_Label_In_Subgraph
+           (Position : in Cursor;
+            Label    : in Edge_Label_Type)
+        return Boolean is
+    begin
+        return False;
+    end Contains_Label_In_Subgraph;
+
+
+
+
+    -------------
+    -- Context --
+    -------------
+
+    procedure Context
+           (Container : in     Graph;
+            Node      : in     Node_Type;
+            Parents   :    out Node_Array;
+            Children  :    out Node_Array) is
+    begin
+        null;
+    end Context;
+
+    procedure Context
+           (Position : in     Cursor;
+            Parents  :    out Node_Array;
+            Children :    out Node_Array) is
+    begin
+        null;
+    end Context;
+
+
+
+
+    ----------
+    -- Copy --
+    ----------
+
+    function Copy
+           (Source : in Graph)
+        return Graph is
+    begin
+        return Empty_Graph;
+    end Copy;
+
+
+
+
+    ------------
+    -- Degree --
+    ------------
+
+    function Degree
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Count_Type is
+    begin
+        return Count_Type'First;
+    end Degree;
+
+    function Degree
+           (Position : in Cursor)
+        return Count_Type is
+    begin
+        return Count_Type'First;
+    end Degree;
+
+
+
+
+    ------------
+    -- Delete --
+    ------------
+
+    procedure Delete
+           (Container : in out Graph;
+            Node      : in     Node_Type) is
+    begin
+        null;
+    end Delete;
+
+    procedure Delete
+           (Position : in out Cursor) is
+    begin
+        null;
+    end Delete;
+
+    procedure Delete
+           (Container : in out Graph;
+            Nodes     : in     Node_Array) is
+    begin
+        null;
+    end Delete;
+
+    procedure Delete
+           (Container : in out Graph;
+            Edge      : in     Edge_Type) is
+    begin
+        null;
+    end Delete;
+
+    procedure Delete
+           (Container : in out Graph;
+            Edges     : in     Edge_Array) is
+    begin
+        null;
+    end Delete;
+
+
+
+
+    ------------------
+    -- Delete_Label --
+    ------------------
+
+    procedure Delete_Label
+           (Container : in out Graph;
+            Node      : in     Node_Type) is
+    begin
+        null;
+    end Delete_Label;
+
+    procedure Delete_Label
+           (Position : in out Cursor) is
+    begin
+        null;
+    end Delete_Label;
+
+    procedure Delete_Label
+           (Container : in out Graph;
+            Edge      : in     Edge_Type) is
+    begin
+        null;
+    end Delete_Label;
+
+
+
+
+    ---------------------
+    -- Delete_Subgraph --
+    ---------------------
+
+    procedure Delete_Subgraph
+           (Position : in out Cursor) is
+    begin
+        null;
+    end Delete_Subgraph;
+
+
+
+
+    ----------------
+    -- Edge_Count --
+    ----------------
+
+    function Edge_Count
+           (Container : in Graph)
+        return Count_Type is
+    begin
+        return Count_Type'First;
+    end Edge_Count;
+
+
+
+
+    -----------
+    -- Edges --
+    -----------
+
+    function Edges
+           (Container : in Graph)
+        return Edge_Array is
+    begin
+        return (others => False);
+    end Edges;
+
+
+
+
+    --------------
+    -- Finalize --
+    --------------
+
+    procedure Finalize
+           (Container : in out Graph) is
+    begin
+        null;
+    end Finalize;
+
+    procedure Finalize
+           (Object : in out Iterator) is
+    begin
+        null;
+    end Finalize;
+
+    procedure Finalize
+           (Object : in out Subgraph_Iterator) is
+    begin
+        null;
+    end Finalize;
+
+
+
+
+    ----------
+    -- Find --
+    ----------
+
+    function Find
+           (Container : in Graph;
+            Label     : in Node_Label_Type)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Find;
+
+    function Find
+           (Container : in Graph;
+            Label     : in Edge_Label_Type)
+        return Edge_Array is
+    begin
+        return (others => False);
+    end Find;
+
+
+
+
+    ----------------------
+    -- Find_In_Subgraph --
+    ----------------------
+
+    function Find_In_Subgraph
+           (Position : in Cursor;
+            Label    : in Node_Label_Type)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Find_In_Subgraph;
+
+    function Find_In_Subgraph
+           (Position : in Cursor;
+            Label    : in Edge_Label_Type)
+        return Edge_Array is
+    begin
+        return (others => False);
+    end Find_In_Subgraph;
+
+
+
+
+    -----------
+    -- First --
+    -----------
+
+    function First
+           (Container : in Graph)
+        return Cursor is
+    begin
+        return No_Element;
+    end First;
+
+    function First
+           (Object : in Iterator)
+        return Cursor is
+    begin
+        return No_Element;
+    end First;
+
+    function First
+           (Object : in Subgraph_Iterator)
+        return Cursor is
+    begin
+        return No_Element;
+    end First;
+
+
+
+
+    --------------
+    -- Has_Edge --
+    --------------
+
+    function Has_Edge
+           (Container     : in Graph;
+            Parent, Child : in Node_Type)
+        return Boolean is
+    begin
+        return False;
+    end Has_Edge;
+
+    function Has_Edge
+           (Parent, Child : in Cursor)
+        return Boolean is
+    begin
+        return False;
+    end Has_Edge;
+
+
+
+
+    -----------------
+    -- Has_Element --
+    -----------------
+
+    function Has_Element
+           (Position : in Cursor)
+        return Boolean is
+    begin
+        return False;
+    end Has_Element;
+
+
+
+
+    ---------------
+    -- Has_Label --
+    ---------------
+
+    function Has_Label
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Boolean is
+    begin
+        return False;
+    end Has_Label;
+
+    function Has_Label
+           (Position : in Cursor)
+        return Boolean is
+    begin
+        return False;
+    end Has_Label;
+
+    function Has_Label
+           (Container : in Graph;
+            Edge      : in Edge_Type)
+        return Boolean is
+    begin
+        return False;
+    end Has_Label;
+
+
+
+
+    ----------------------
+    -- Has_Labeled_Edge --
+    ----------------------
+
+    function Has_Labeled_Edge
+           (Container     : in Graph;
+            Parent, Child : Node_Type)
+        return Boolean is
+    begin
+        return False;
+    end Has_Labeled_Edge;
+
+    function Has_Labeled_Edge
+           (Parent, Child : in Cursor)
+        return Boolean is
+    begin
+        return False;
+    end Has_Labeled_Edge;
+
+
+
+
+    ------------------
+    -- Has_Neighbor --
+    ------------------
+
+    function Has_Neighbor
+           (Container   : in Graph;
+            Left, Right : in Node_Type)
+        return Boolean is
+    begin
+        return False;
+    end Has_Neighbor;
+
+    function Has_Neighbor
+           (Left, Right : in Cursor)
+        return Boolean is
+    begin
+        return False;
+    end Has_Neighbor;
+
+
+
+
+    -------------
+    -- Inbound --
+    -------------
+
+    function Inbound
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Edge_Array is
+    begin
+        return (others => False);
+    end Inbound;
+
+    function Inbound
+           (Position : in Cursor)
+        return Edge_Array is
+    begin
+        return (others => False);
+    end Inbound;
+
+
+
+
+    --------------
+    -- Indegree --
+    --------------
+
+    function Indegree
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Count_Type is
+    begin
+        return Count_Type'First;
+    end Indegree;
+
+    function Indegree
+           (Position : in Cursor)
+        return Count_Type is
+    begin
+        return Count_Type'First;
+    end Indegree;
+
+
+
+
+    ------------
+    -- Insert --
+    ------------
+
+    procedure Insert
+           (Container : in out Graph;
+            Node      : in     Node_Type) is
+    begin
+        null;
+    end Insert;
+
+    procedure Insert
+           (Container : in out Graph;
+            Node      : in     Node_Type;
+            Label     : in     Node_Label_Type) is
+    begin
+        null;
+    end Insert;
+
+    procedure Insert
+           (Container : in out Graph;
+            Nodes     : in     Node_Array) is
+    begin
+        null;
+    end Insert;
+
+    procedure Insert
+           (Container : in out Graph;
+            Edge      : in     Edge_Type) is
+    begin
+        null;
+    end Insert;
+
+    procedure Insert
+           (Container : in out Graph;
+            Edge      : in     Edge_Type;
+            Label     : in     Edge_Label_Type) is
+    begin
+        null;
+    end Insert;
+
+    procedure Insert
+           (Container : in out Graph;
+            Edges     : in     Edge_Array) is
+    begin
+        null;
+    end Insert;
+
+
+
+
+    --------------
+    -- Is_Empty --
+    --------------
+
+    function Is_Empty
+           (Container : in Graph)
+        return Boolean is
+    begin
+        return True;
+    end Is_Empty;
+
+
+
+
+    -------------
+    -- Iterate --
+    -------------
+
+    function Iterate
+           (Container : in Graph)
+        return Graph_Iterator_Interfaces.Reversible_Iterator'Class is
+    begin
+        return It : Iterator :=
+           (Ada.Finalization.Limited_Controlled with
+            Container => null,
+            Node => Extended_Node_Type'First);
+    end Iterate;
+
+
+
+
+    ----------------------
+    -- Iterate_Subgraph --
+    ----------------------
+
+    function Iterate_Subgraph
+           (Container : in Graph;
+            Position  : in Cursor)
+        return Graph_Iterator_Interfaces.Forward_Iterator'Class is
+    begin
+        return It : Subgraph_Iterator :=
+           (Ada.Finalization.Limited_Controlled with
+            Container => null,
+            Root_Node => Node_Type'First,
+            Visited => Node_Vectors.Empty_Vector,
+            Current => Extended_Node_Type'First);
+    end Iterate_Subgraph;
+
+
+
+
+    -----------
+    -- Label --
+    -----------
+
+    function Label
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Node_Label_Type is
+    begin
+        return Node_Label_Type'(others => <>);
+    end Label;
+
+    function Label
+           (Position : in Cursor)
+        return Node_Label_Type is
+    begin
+        return Node_Label_Type'(others => <>);
+    end Label;
+
+    function Label
+           (Container : in Graph;
+            Edge      : in Edge_Type)
+        return Edge_Label_Type is
+    begin
+        return Edge_Label_Type'(others => <>);
+    end Label;
+
+
+
+
+    ---------------------
+    -- Label_Reference --
+    ---------------------
+
+    function Label_Reference
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Node_Label_Reference is
+    begin
+        return R : Node_Label_Reference :=
+           (Element => null;
+            Control => (Ada.Finalization.Controlled with null));
+    end Label_Reference;
+
+    function Label_Reference
+           (Position : in Cursor)
+        return Node_Label_Reference is
+    begin
+        return R : Node_Label_Reference :=
+           (Element => null;
+            Control => (Ada.Finalization.Controlled with null));
+    end Label_Reference;
+
+    function Label_Reference
+           (Container : in Graph;
+            Edge      : in Edge_Type)
+        return Edge_Label_Reference is
+    begin
+        return R : Edge_Label_Reference :=
+           (Element => null;
+            Control => (Ada.Finalization.Controlled with null));
+    end Label_Reference;
+
+
+
+
+    ---------------------
+    -- Labeled_Context --
+    ---------------------
+
+    procedure Labeled_Context
+           (Container : in     Graph;
+            Node      : in     Node_Type;
+            Parents   :    out Node_Array;
+            Children  :    out Node_Array;
+            Label     :    out Node_Label_Type) is
+    begin
+        null;
+    end Labeled_Context;
+
+    procedure Labeled_Context
+           (Position : in     Cursor;
+            Parents  :    out Node_Array;
+            Children :    out Node_Array;
+            Label    :    out Node_Label_Type) is
+    begin
+        null;
+    end Labeled_Context;
+
+
+
+
+    ----------
+    -- Last --
+    ----------
+
+    function Last
+           (Container : in Graph)
+        return Cursor is
+    begin
+        return No_Element;
+    end Last;
+
+    function Last
+           (Object : in Iterator)
+        return Cursor is
+    begin
+        return No_Element;
+    end Last;
+
+
+
+
+    ----------
+    -- Move --
+    ----------
+
+    procedure Move
+           (Target, Source : in out Graph) is
+    begin
+        null;
+    end Move;
+
+
+
+
+    ---------------
+    -- Neighbors --
+    ---------------
+
+    function Neighbors
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Neighbors;
+
+    function Neighbors
+           (Position : in Cursor)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Neighbors;
+
+
+
+
+    ----------
+    -- Next --
+    ----------
+
+    function Next
+           (Position : in Cursor)
+        return Cursor is
+    begin
+        return No_Element;
+    end Next;
+
+    procedure Next
+           (Position : in out Cursor) is
+    begin
+        null;
+    end Next;
+
+    function Next
+           (Object   : in Iterator;
+            Position : in Cursor)
+        return Cursor is
+    begin
+        return No_Element;
+    end Next;
+
+    function Next
+           (Object   : in Subgraph_Iterator;
+            Position : in Cursor)
+        return Cursor is
+    begin
+        return No_Element;
+    end Next;
+
+
+
+
+    ----------------
+    -- Node_Count --
+    ----------------
+
+    function Node_Count
+           (Container : in Graph)
+        return Count_Type is
+    begin
+        return Count_Type'First;
+    end Node_Count;
+
+
+
+
+    ----------------
+    -- Node_Range --
+    ----------------
+
+    procedure Node_Range
+           (Container : in     Graph;
+            Minimum   :    out Node;
+            Maximum   :    out Node) is
+    begin
+        null;
+    end Node_Range;
+
+
+
+
+    -----------
+    -- Nodes --
+    -----------
+
+    function Nodes
+           (Container : in Graph)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Nodes;
+
+
+
+
+    --------------
+    -- Outbound --
+    --------------
+
+    function Outbound
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Edge_Array is
+    begin
+        return (others => False);
+    end Outbound;
+
+    function Outbound
+           (Position : in Cursor)
+        return Edge_Array is
+    begin
+        return (others => False);
+    end Outbound;
+
+
+
+
+    ---------------
+    -- Outdegree --
+    ---------------
+
+    function Outdegree
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Count_Type is
+    begin
+        return Count_Type'First;
+    end Outdegree;
+
+    function Outdegree
+           (Position : in Cursor)
+        return Count_Type is
+    begin
+        return Count_Type'First;
+    end Outdegree;
+
+
+
+
+    -------------
+    -- Parents --
+    -------------
+
+    function Parents
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Parents;
+
+    function Parents
+           (Position : in Cursor)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Parents;
+
+
+
+
+    --------------
+    -- Previous --
+    --------------
+
+    function Previous
+           (Position : in Cursor)
+        return Cursor is
+    begin
+        return No_Element;
+    end Previous;
+
+    procedure Previous
+           (Position : in out Cursor) is
+    begin
+        null;
+    end Previous;
+
+    function Previous
+           (Object   : in Iterator;
+            Position : in Cursor)
+        return Cursor is
+    begin
+        return No_Element;
+    end Previous;
+
+
+
+
+    ----------
+    -- Read --
+    ----------
+
+    procedure Read
+           (Stream    : not null access Streams.Root_Stream_Type'Class;
+            Container :    out          Graph) is
+    begin
+        null;
+    end Read;
+
+    procedure Read
+           (Stream   : not null access Streams.Root_Stream_Type'Class;
+            Position :    out          Cursor) is
+    begin
+        null;
+    end Read;
+
+    procedure Read
+           (Stream : not null access Streams.Root_Stream_Type'Class;
+            Item   :    out          Node_Label_Constant_Reference) is
+    begin
+        null;
+    end Read;
+
+    procedure Read
+           (Stream : not null access Streams.Root_Stream_Type'Class;
+            Item   :    out          Node_Label_Reference) is
+    begin
+        null;
+    end Read;
+
+    procedure Read
+           (Stream : not null access Streams.Root_Stream_Type'Class;
+            Item   :    out          Edge_Label_Constant_Reference) is
+    begin
+        null;
+    end Read;
+
+    procedure Read
+           (Stream : not null access Streams.Root_Stream_Type'Class;
+            Item   :    out          Edge_Label_Reference) is
+    begin
+        null;
+    end Read;
+
+
+
+
+    -------------------
+    -- Replace_Label --
+    -------------------
+
+    procedure Replace_Label
+           (Container : in out Graph;
+            Node      : in     Node_Type;
+            Label     : in     Node_Label_Type) is
+    begin
+        null;
+    end Replace_Label;
+
+    procedure Replace_Label
+           (Position : in out Cursor;
+            Label    : in     Node_Label_Type) is
+    begin
+        null;
+    end Replace_Label;
+
+    procedure Replace_Label
+           (Container : in out Graph;
+            Edge      : in     Edge_Type;
+            Label     : in     Edge_Label_Type) is
+    begin
+        null;
+    end Replace_Label;
+
+
+
+
+    ----------
+    -- Swap --
+    ----------
+
+    procedure Swap
+           (Container   : in out Graph;
+            Left, Right : in     Node_Type) is
+    begin
+        null;
+    end Swap;
+
+    procedure Swap
+           (Left, Right : in out Cursor) is
+    begin
+        null;
+    end Swap;
+
+
+
+
+    ---------------
+    -- To_Cursor --
+    ---------------
+
+    function To_Cursor
+           (Container : in Graph;
+            Node      : in Node_Type)
+        return Cursor;
+
+
+
+
+    --------------
+    -- To_Graph --
+    --------------
+
+    function To_Graph
+           (Nodes : in Node_Array;
+            Edges : in Edge_Array)
+        return Graph is
+    begin
+        return Empty_Graph;
+    end To_Graph;
+
+
+
+
+    -------------
+    -- To_Hash --
+    -------------
+
+    function To_Hash
+           (Node : in Node_Type)
+        return Hash_Type is
+    begin
+        return Hash_Type'First;
+    end To_Hash;
+
+    function To_Hash
+           (Edge : in Edge_Type)
+        return Hash_Type is
+    begin
+        return Hash_Type'First;
+    end To_Hash;
+
+
+
+
+    ------------------
+    -- Unused_Nodes --
+    ------------------
+
+    function Unused_Nodes
+           (Container : in Graph;
+            Count     : in Positive := 1)
+        return Node_Array is
+    begin
+        return (others => False);
+    end Unused_Nodes;
+
+
+
+
+    -----------
+    -- Write --
+    -----------
+
+    procedure Write
+           (Stream    : not null access Streams.Root_Stream_Type'Class;
+            Container : in              Graph) is
+    begin
+        null;
+    end Write;
+
+    procedure Write
+           (Stream   : not null access Streams.Root_Stream_Type'Class;
+            Position : in              Cursor) is
+    begin
+        null;
+    end Write;
+
+    procedure Write
+           (Stream : not null access Streams.Root_Stream_Type'Class;
+            Item   : in              Node_Label_Constant_Reference) is
+    begin
+        null;
+    end Write;
+
+    procedure Write
+           (Stream : not null access Streams.Root_Stream_Type'Class;
+            Item   : in              Node_Label_Reference) is
+    begin
+        null;
+    end Write;
+
+    procedure Write
+           (Stream : not null access Streams.Root_Stream_Type'Class;
+            Item   : in              Edge_Label_Constant_Reference) is
+    begin
+        null;
+    end Write;
+
+    procedure Write
+           (Stream : not null access Streams.Root_Stream_Type'Class;
+            Item   : in              Edge_Label_Reference) is
+    begin
+        null;
+    end Write;
+
+
+end Ada.Containers.Directed_Graphs;
+
+
diff --git a/src/ada-containers-directed_graphs.ads b/src/ada-containers-directed_graphs.ads
index 83ab249..f248bd6 100644
--- a/src/ada-containers-directed_graphs.ads
+++ b/src/ada-containers-directed_graphs.ads
@@ -784,7 +784,7 @@ private
 
     overriding function Next
            (Object   : in Subgraph_Iterator;
-            Position : in Subgraph_Iterator)
+            Position : in Cursor)
         return Cursor;