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authorJed Barber <jjbarber@y7mail.com>2020-04-29 00:20:09 +1000
committerJed Barber <jjbarber@y7mail.com>2020-04-29 00:20:09 +1000
commit0966aadcc0e95ddb1fc5e3edfbefe0aaf64d2f76 (patch)
tree68366ef8fa601454b92fa804b145975028d1870f /src
parent2551080276e30000767a318c1896db1eaa506fcc (diff)
Rough refactor of Cursors and Iterators
Diffstat (limited to 'src')
-rw-r--r--src/directed_graphs.adb329
-rw-r--r--src/directed_graphs.ads25
2 files changed, 217 insertions, 137 deletions
diff --git a/src/directed_graphs.adb b/src/directed_graphs.adb
index a17f1d4..93ad2cb 100644
--- a/src/directed_graphs.adb
+++ b/src/directed_graphs.adb
@@ -92,6 +92,7 @@ package body Directed_Graphs is
Position : out Cursor)
is
Node : Node_Type := Node_Type'First;
+ Insert_Success : Boolean;
begin
while Container.Connections.Contains (Node) loop
if Impl.Checks and then Node = Node_Type'Last then
@@ -99,9 +100,13 @@ package body Directed_Graphs is
end if;
Node := Node_Type'Succ (Node);
end loop;
- Container.Connections.Insert (Node, Node_Vectors.Empty_Vector);
+ Container.Connections.Insert
+ (Node, Node_Vectors.Empty_Vector, Position.Place, Insert_Success);
+ if Impl.Checks and then not Insert_Success then
+ raise Program_Error with "Graph Insert failed";
+ end if;
Position.Container := Container'Unrestricted_Access;
- Position.Node := Node;
+ Position.Sub_Index := Node_Vectors.Extended_Index'First;
end Append;
procedure Append
@@ -110,7 +115,7 @@ package body Directed_Graphs is
Position : out Cursor) is
begin
Container.Append (Position);
- Container.Node_Labels.Insert (Position.Node, Label);
+ Container.Node_Labels.Insert (Element (Position), Label);
end Append;
@@ -139,7 +144,10 @@ package body Directed_Graphs is
(Position : in out Cursor;
Label : in Node_Label_Type) is
begin
- Position.Container.Append_Label (Position.Node, Label);
+ if Impl.Checks and then Position.Container = null then
+ raise Constraint_Error with "Graph does not exist";
+ end if;
+ Position.Container.Append_Label (Element (Position), Label);
end Append_Label;
procedure Append_Label
@@ -196,7 +204,10 @@ package body Directed_Graphs is
(Position : in Cursor)
return Node_Array is
begin
- return Position.Container.Children (Position.Node);
+ if Impl.Checks and then Position.Container = null then
+ raise Constraint_Error with "Graph does not exist";
+ end if;
+ return Position.Container.Children (Element (Position));
end Children;
@@ -266,7 +277,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Node_Label_Constant_Reference is
begin
- return Position.Container.Constant_Label_Reference (Position.Node);
+ return Position.Container.Constant_Label_Reference (Element (Position));
end Constant_Label_Reference;
function Constant_Label_Reference
@@ -356,7 +367,7 @@ package body Directed_Graphs is
return False;
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- if C.Node = Node then
+ if Element (C) = Node then
return True;
end if;
end loop;
@@ -373,7 +384,7 @@ package body Directed_Graphs is
return False;
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- if C.Node = Node and Constant_Label_Reference (C) = Label then
+ if Element (C) = Node and Constant_Label_Reference (C) = Label then
return True;
end if;
end loop;
@@ -393,10 +404,10 @@ package body Directed_Graphs is
return False;
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- if C.Node = Edge.From then
+ if Element (C) = Edge.From then
Parent_Check := True;
end if;
- if C.Node = Edge.To then
+ if Element (C) = Edge.To then
Child_Check := True;
end if;
if Parent_Check and Child_Check then
@@ -420,10 +431,10 @@ package body Directed_Graphs is
return False;
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- if C.Node = Edge.From then
+ if Element (C) = Edge.From then
Parent_Check := True;
end if;
- if C.Node = Edge.To then
+ if Element (C) = Edge.To then
Child_Check := True;
end if;
if Parent_Check and Child_Check then
@@ -484,7 +495,7 @@ package body Directed_Graphs is
return False;
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- if Position.Container.Node_Labels.Contains (C.Node) then
+ if Position.Container.Node_Labels.Contains (Element (C)) then
return True;
end if;
end loop;
@@ -505,7 +516,7 @@ package body Directed_Graphs is
return False;
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- Inside.Append (C.Node);
+ Inside.Append (Element (C));
end loop;
for E in Position.Container.Edge_Labels.Iterate loop
Check := Edge_Label_Maps.Key (E);
@@ -541,7 +552,15 @@ package body Directed_Graphs is
Parents : out Node_Array;
Children : out Node_Array) is
begin
- Position.Container.Context (Position.Node, Parents, Children);
+ if Impl.Checks then
+ if Position.Container = null then
+ raise Constraint_Error with "Graph does not exist";
+ end if;
+ if not Has_Element (Position) then
+ raise Constraint_Error with "Cursor points to nothing";
+ end if;
+ end if;
+ Position.Container.Context (Element (Position), Parents, Children);
end Context;
@@ -583,7 +602,15 @@ package body Directed_Graphs is
(Position : in Cursor)
return Ada.Containers.Count_Type is
begin
- return Position.Container.Degree (Position.Node);
+ if Impl.Checks then
+ if Position.Container = null then
+ raise Constraint_Error with "Graph does not exist";
+ end if;
+ if not Has_Element (Position) then
+ raise Constraint_Error with "Cursor points to nothing";
+ end if;
+ end if;
+ return Position.Container.Degree (Element (Position));
end Degree;
@@ -624,7 +651,15 @@ package body Directed_Graphs is
procedure Delete
(Position : in out Cursor) is
begin
- Position.Container.Delete (Position.Node);
+ if Impl.Checks then
+ if Position.Container = null then
+ raise Constraint_Error with "Graph does not exist";
+ end if;
+ if not Has_Element (Position) then
+ raise Constraint_Error with "Cursor points to nothing";
+ end if;
+ end if;
+ Position.Container.Delete (Element (Position));
end Delete;
procedure Delete
@@ -678,7 +713,15 @@ package body Directed_Graphs is
procedure Delete_Label
(Position : in out Cursor) is
begin
- Position.Container.Delete_Label (Position.Node);
+ if Impl.Checks then
+ if Position.Container = null then
+ raise Constraint_Error with "Graph does not exist";
+ end if;
+ if not Has_Element (Position) then
+ raise Constraint_Error with "Cursor points to nothing";
+ end if;
+ end if;
+ Position.Container.Delete_Label (Element (Position));
end Delete_Label;
procedure Delete_Label
@@ -705,7 +748,7 @@ package body Directed_Graphs is
raise Constraint_Error with "Graph does not exist";
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- Nodes.Append (C.Node);
+ Nodes.Append (Element (C));
end loop;
Position.Container.Delete (V2A (Nodes));
end Delete_Subgraph;
@@ -799,10 +842,15 @@ package body Directed_Graphs is
(Position : in Cursor)
return Node_Type is
begin
- if Impl.Checks and then Position.Container = null then
- raise Constraint_Error with "Graph does not exist";
+ if Impl.Checks then
+ if Position.Container = null then
+ raise Constraint_Error with "Graph does not exist";
+ end if;
+ if not Has_Element (Position) then
+ raise Constraint_Error with "Cursor points to nothing";
+ end if;
end if;
- return Position.Node;
+ return Node_Maps.Key (Position.Place);
end Element;
@@ -888,8 +936,8 @@ package body Directed_Graphs is
raise Constraint_Error with "Graph does not exist";
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- if Position.Container.Node_Labels.Constant_Reference (C.Node) = Label then
- Result.Append (C.Node);
+ if Position.Container.Node_Labels.Constant_Reference (Element (C)) = Label then
+ Result.Append (Element (C));
end if;
end loop;
return V2A (Result);
@@ -909,7 +957,7 @@ package body Directed_Graphs is
raise Constraint_Error with "Graph does not exist";
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- Nodes.Append (C.Node);
+ Nodes.Append (Element (C));
end loop;
for E of Keys (Position.Container.Edge_Labels) loop
if Nodes.Contains (E.From) and then
@@ -934,22 +982,14 @@ package body Directed_Graphs is
return Cursor
is
use type Ada.Containers.Count_Type;
- Node : Node_Type := Node_Type'Last;
- function Keys is new Key_Vector (Node_Type, Node_Vectors.Vector, Node_Maps, Node_Vectors);
begin
if Impl.Checks and then Container.Node_Count = 0 then
raise Constraint_Error with "Graph is empty";
end if;
- for N of Keys (Container.Connections) loop
- if N < Node then
- Node := N;
- end if;
- end loop;
return
(Container => Container'Unrestricted_Access,
- Node => Node,
- Visited => Node_Vectors.Empty_Vector,
- Path_Up => Node_Vectors.Empty_Vector);
+ Place => Container.Connections.First,
+ Sub_Index => Node_Vectors.Extended_Index'First);
end First;
function First
@@ -963,11 +1003,14 @@ package body Directed_Graphs is
(Object : in Subgraph_Iterator)
return Cursor is
begin
- return
- (Container => Object.Container,
- Node => Object.Root_Node,
- Visited => Node_Vectors.Empty_Vector,
- Path_Up => Node_Vectors.Empty_Vector);
+ if Object.Nodes.Is_Empty then
+ return No_Element;
+ else
+ return
+ (Container => Object.Container,
+ Place => Object.Container.Connections.Find (Object.Nodes.First_Element),
+ Sub_Index => Object.Nodes.First_Index);
+ end if;
end First;
@@ -996,7 +1039,7 @@ package body Directed_Graphs is
(Parent, Child : in Cursor)
return Boolean is
begin
- return Parent.Container.Has_Edge (Parent.Node, Child.Node);
+ return Parent.Container.Has_Edge (Element (Parent), Element (Child));
end Has_Edge;
@@ -1011,7 +1054,7 @@ package body Directed_Graphs is
return Boolean is
begin
return Position.Container /= null and then
- Position.Container.Contains (Position.Node);
+ Position.Container.Contains (Node_Maps.Key (Position.Place));
end Has_Element;
@@ -1033,7 +1076,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Boolean is
begin
- return Position.Container.Has_Label (Position.Node);
+ return Position.Container.Has_Label (Element (Position));
end Has_Label;
function Has_Label
@@ -1064,7 +1107,7 @@ package body Directed_Graphs is
(Parent, Child : in Cursor)
return Boolean is
begin
- return Parent.Container.Has_Labeled_Edge (Parent.Node, Child.Node);
+ return Parent.Container.Has_Labeled_Edge (Element (Parent), Element (Child));
end Has_Labeled_Edge;
@@ -1087,7 +1130,7 @@ package body Directed_Graphs is
(Left, Right : in Cursor)
return Boolean is
begin
- return Left.Container.Has_Neighbor (Left.Node, Right.Node);
+ return Left.Container.Has_Neighbor (Element (Left), Element (Right));
end Has_Neighbor;
@@ -1122,7 +1165,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Edge_Array is
begin
- return Position.Container.Inbound (Position.Node);
+ return Position.Container.Inbound (Element (Position));
end Inbound;
@@ -1155,7 +1198,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Ada.Containers.Count_Type is
begin
- return Position.Container.Indegree (Position.Node);
+ return Position.Container.Indegree (Element (Position));
end Indegree;
@@ -1266,11 +1309,38 @@ package body Directed_Graphs is
function Iterate_Subgraph
(Container : in Graph;
Position : in Cursor)
- return Graph_Iterator_Interfaces.Forward_Iterator'Class is
+ return Graph_Iterator_Interfaces.Forward_Iterator'Class
+ is
+ Root_Node, Current_Node : Node_Type;
+ Path_Up : Node_Vectors.Vector;
+ Visited : Node_Vectors.Vector;
begin
+ if Impl.Checks and then not Has_Element (Position) then
+ raise Constraint_Error with "Cursor points to nothing";
+ end if;
+ Root_Node := Element (Position);
+ Current_Node := Root_Node;
+ Depth_First : loop
+ Visited.Append (Current_Node);
+ Select_Next : loop
+ for N of Container.Children (Current_Node) loop
+ if not Visited.Contains (N) then
+ Path_Up.Append (Current_Node);
+ Current_Node := N;
+ exit Select_Next;
+ end if;
+ end loop;
+ if Path_Up.Is_Empty then
+ exit Depth_First;
+ else
+ Current_Node := Path_Up.Last_Element;
+ Path_Up.Delete_Last;
+ end if;
+ end loop Select_Next;
+ end loop Depth_First;
return It : Subgraph_Iterator do
It.Container := Container'Unrestricted_Access;
- It.Root_Node := Position.Node;
+ It.Nodes := Visited;
end return;
end Iterate_Subgraph;
@@ -1318,7 +1388,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Node_Label_Type is
begin
- return Position.Container.Label (Position.Node);
+ return Position.Container.Label (Element (Position));
end Label;
function Label
@@ -1372,7 +1442,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Node_Label_Reference is
begin
- return Position.Container.Label_Reference (Position.Node);
+ return Position.Container.Label_Reference (Element (Position));
end Label_Reference;
function Label_Reference
@@ -1425,7 +1495,7 @@ package body Directed_Graphs is
Children : out Node_Array;
Label : out Node_Label_Type) is
begin
- Position.Container.Labeled_Context (Position.Node, Parents, Children, Label);
+ Position.Container.Labeled_Context (Element (Position), Parents, Children, Label);
end Labeled_Context;
@@ -1437,25 +1507,16 @@ package body Directed_Graphs is
function Last
(Container : in Graph)
- return Cursor
- is
- use type Ada.Containers.Count_Type;
- Node : Node_Type := Node_Type'First;
- function Keys is new Key_Vector (Node_Type, Node_Vectors.Vector, Node_Maps, Node_Vectors);
+ return Cursor is
begin
- if Impl.Checks and then Container.Node_Count = 0 then
- raise Constraint_Error with "Graph is empty";
+ if Container.Is_Empty then
+ return No_Element;
+ else
+ return
+ (Container => Container'Unrestricted_Access,
+ Place => Container.Connections.Last,
+ Sub_Index => Node_Vectors.Extended_Index'First);
end if;
- for N of Keys (Container.Connections) loop
- if N > Node then
- Node := N;
- end if;
- end loop;
- return
- (Container => Container'Unrestricted_Access,
- Node => Node,
- Visited => Node_Vectors.Empty_Vector,
- Path_Up => Node_Vectors.Empty_Vector);
end Last;
function Last
@@ -1465,6 +1526,20 @@ package body Directed_Graphs is
return Object.Container.Last;
end Last;
+ function Last
+ (Object : in Subgraph_Iterator)
+ return Cursor is
+ begin
+ if Object.Nodes.Is_Empty then
+ return No_Element;
+ else
+ return
+ (Container => Object.Container,
+ Place => Object.Container.Connections.Find (Object.Nodes.Last_Element),
+ Sub_Index => Object.Nodes.Last_Index);
+ end if;
+ end Last;
+
@@ -1513,7 +1588,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Node_Array is
begin
- return Position.Container.Neighbors (Position.Node);
+ return Position.Container.Neighbors (Element (Position));
end Neighbors;
@@ -1534,26 +1609,13 @@ package body Directed_Graphs is
end Next;
procedure Next
- (Position : in out Cursor)
- is
- Select_From : Node_Vectors.Vector;
- Current_Index : Natural;
- function Keys is new Key_Vector (Node_Type, Node_Vectors.Vector, Node_Maps, Node_Vectors);
+ (Position : in out Cursor) is
begin
if Position.Container = null then
Position := No_Element;
return;
end if;
- Select_From := Keys (Position.Container.Connections);
- Node_Sort.Sort (Select_From);
- Current_Index := Select_From.Find_Index (Position.Node);
- if Current_Index = Node_Vectors.No_Index or
- Current_Index = Select_From.Last_Index
- then
- Position := No_Element;
- else
- Position.Node := Select_From (Current_Index + 1);
- end if;
+ Node_Maps.Next (Position.Place);
end Next;
function Next
@@ -1572,30 +1634,27 @@ package body Directed_Graphs is
Position : in Cursor)
return Cursor
is
- Next_Cursor : Cursor := Position;
- Consider : Node_Vectors.Vector;
+ use type Node_Maps.Cursor;
+ Result : Cursor := Position;
begin
- if Position.Container = null then
+ if Position.Container = null or Position.Place = Node_Maps.No_Element then
return No_Element;
end if;
- Next_Cursor.Visited.Append (Position.Node);
- loop
- Consider := Next_Cursor.Container.Connections.Constant_Reference (Next_Cursor.Node);
- Node_Sort.Sort (Consider);
- for N of Consider loop
- if not Next_Cursor.Visited.Contains (N) then
- Next_Cursor.Path_Up.Append (Next_Cursor.Node);
- Next_Cursor.Node := N;
- return Next_Cursor;
- end if;
- end loop;
- if Next_Cursor.Path_Up.Is_Empty then
+ if Position.Sub_Index not in 1 .. Object.Nodes.Last_Index or else
+ Node_Maps.Key (Position.Place) /= Object.Nodes (Position.Sub_Index)
+ then
+ Result.Sub_Index := Object.Nodes.Find_Index (Node_Maps.Key (Position.Place));
+ if Result.Sub_Index = Node_Vectors.No_Index then
return No_Element;
- else
- Next_Cursor.Node := Next_Cursor.Path_Up.Last_Element;
- Next_Cursor.Path_Up.Delete_Last;
end if;
- end loop;
+ end if;
+ if Result.Sub_Index = Object.Nodes.Last_Index then
+ return No_Element;
+ else
+ Result.Sub_Index := Result.Sub_Index + 1;
+ Result.Place := Result.Container.Connections.Find (Object.Nodes (Result.Sub_Index));
+ return Result;
+ end if;
end Next;
@@ -1683,7 +1742,7 @@ package body Directed_Graphs is
raise Constraint_Error with "Graph does not exist";
end if;
for C in Position.Container.Iterate_Subgraph (Position) loop
- Result.Append (C.Node);
+ Result.Append (Element (C));
end loop;
return V2A (Result);
end Nodes;
@@ -1721,7 +1780,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Edge_Array is
begin
- return Position.Container.Outbound (Position.Node);
+ return Position.Container.Outbound (Element (Position));
end Outbound;
@@ -1747,7 +1806,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Ada.Containers.Count_Type is
begin
- return Position.Container.Outdegree (Position.Node);
+ return Position.Container.Outdegree (Element (Position));
end Outdegree;
@@ -1781,7 +1840,7 @@ package body Directed_Graphs is
(Position : in Cursor)
return Node_Array is
begin
- return Position.Container.Parents (Position.Node);
+ return Position.Container.Parents (Element (Position));
end Parents;
@@ -1802,26 +1861,13 @@ package body Directed_Graphs is
end Previous;
procedure Previous
- (Position : in out Cursor)
- is
- Select_From : Node_Vectors.Vector;
- Current_Index : Natural;
- function Keys is new Key_Vector (Node_Type, Node_Vectors.Vector, Node_Maps, Node_Vectors);
+ (Position : in out Cursor) is
begin
if Position.Container = null then
Position := No_Element;
return;
end if;
- Select_From := Keys (Position.Container.Connections);
- Node_Sort.Sort (Select_From);
- Current_Index := Select_From.Find_Index (Position.Node);
- if Current_Index = Node_Vectors.No_Index or
- Current_Index = Select_From.First_Index
- then
- Position := No_Element;
- else
- Position.Node := Select_From (Current_Index - 1);
- end if;
+ Node_Maps.Previous (Position.Place);
end Previous;
function Previous
@@ -1835,6 +1881,34 @@ package body Directed_Graphs is
return Cursor_Copy;
end Previous;
+ function Previous
+ (Object : in Subgraph_Iterator;
+ Position : in Cursor)
+ return Cursor
+ is
+ use type Node_Maps.Cursor;
+ Result : Cursor := Position;
+ begin
+ if Position.Container = null or Position.Place = Node_Maps.No_Element then
+ return No_Element;
+ end if;
+ if Position.Sub_Index not in 1 .. Object.Nodes.Last_Index or else
+ Node_Maps.Key (Position.Place) /= Object.Nodes (Position.Sub_Index)
+ then
+ Result.Sub_Index := Object.Nodes.Find_Index (Node_Maps.Key (Position.Place));
+ if Result.Sub_Index = Node_Vectors.No_Index then
+ return No_Element;
+ end if;
+ end if;
+ if Result.Sub_Index = Object.Nodes.First_Index then
+ return No_Element;
+ else
+ Result.Sub_Index := Result.Sub_Index - 1;
+ Result.Place := Result.Container.Connections.Find (Object.Nodes (Result.Sub_Index));
+ return Result;
+ end if;
+ end Previous;
+
@@ -1906,7 +1980,7 @@ package body Directed_Graphs is
(Position : in out Cursor;
Label : in Node_Label_Type) is
begin
- Position.Container.Replace_Label (Position.Node, Label);
+ Position.Container.Replace_Label (Element (Position), Label);
end Replace_Label;
procedure Replace_Label
@@ -1982,7 +2056,7 @@ package body Directed_Graphs is
raise Constraint_Error with "Right operand graph does not exist";
end if;
end if;
- Left.Container.Swap (Left.Node, Right.Node);
+ Left.Container.Swap (Element (Left), Element (Right));
end Swap;
@@ -2002,9 +2076,8 @@ package body Directed_Graphs is
else
return
(Container => Container'Unrestricted_Access,
- Node => Node,
- Visited => Node_Vectors.Empty_Vector,
- Path_Up => Node_Vectors.Empty_Vector);
+ Place => Container.Connections.Find (Node),
+ Sub_Index => Node_Vectors.Extended_Index'First);
end if;
end To_Cursor;
diff --git a/src/directed_graphs.ads b/src/directed_graphs.ads
index 77d9850..7039d76 100644
--- a/src/directed_graphs.ads
+++ b/src/directed_graphs.ads
@@ -682,9 +682,8 @@ private
type Cursor is record
Container : Graph_Access;
- Node : Node_Type := Node_Type'First;
- Visited : Node_Vectors.Vector;
- Path_Up : Node_Vectors.Vector;
+ Place : Node_Maps.Cursor;
+ Sub_Index : Node_Vectors.Extended_Index;
end record;
procedure Write
@@ -698,10 +697,9 @@ private
for Cursor'Read use Read;
No_Element : constant Cursor :=
- (Container => null,
- Node => Node_Type'First,
- Visited => Node_Vectors.Empty_Vector,
- Path_Up => Node_Vectors.Empty_Vector);
+ (Container => null,
+ Place => Node_Maps.No_Element,
+ Sub_Index => Node_Vectors.Extended_Index'First);
@@ -811,10 +809,10 @@ private
type Subgraph_Iterator is new Ada.Finalization.Limited_Controlled and
- Graph_Iterator_Interfaces.Forward_Iterator with
+ Graph_Iterator_Interfaces.Reversible_Iterator with
record
Container : Graph_Access;
- Root_Node : Node_Type;
+ Nodes : Node_Vectors.Vector;
end record
with Disable_Controlled => not Impl.T_Check;
@@ -825,11 +823,20 @@ private
(Object : in Subgraph_Iterator)
return Cursor;
+ overriding function Last
+ (Object : in Subgraph_Iterator)
+ return Cursor;
+
overriding function Next
(Object : in Subgraph_Iterator;
Position : in Cursor)
return Cursor;
+ overriding function Previous
+ (Object : in Subgraph_Iterator;
+ Position : in Cursor)
+ return Cursor;
+
end Directed_Graphs;