anchor.diff:                  if (edges.[i]|>fun (s,t,w) -> t) = target then Some edges.[i]  else loop (i+1)
               loop 0                
       
  -    // Lookup all edges in the graph that matches the conditions, returning a Some value if it exists and None if not.
  +    ///Return the first edge in the graph that matches the conditions.
  +    member this.getEdge((source:'Vertex),(target:'Vertex)) :LEdge<'Vertex,'Edge> =
  +        match (this.TryGetEdge(source,target)) with
  +            |Some x -> x
  +            |None   -> failwith "Edge does not exist"
  +
  +    ///Lookup all edges in the graph that matches the conditions, returning a Some value if it exists and None if not.
       member this.TryGetEdges((source:'Vertex),(target:'Vertex)) :LEdge<'Vertex,'Edge> list option=
           let tryGetSource =
               Dictionary.tryGetValue source vertexOutEdges
  
positive.code:             
              let _edges = loop 0 []
              if  _edges = List.empty then None
              else Some _edges   
      
      // Lookup all edges that originate the vertex v in the graph, returning a Some value if a binding exists and None if not.
      member this.TryGetOutEdges((v:'Vertex)) =
          let tryGetSource = (Dictionary.tryGetValue v vertexOutEdges)
          
  
negative.code:     //        | Some x -> x
      //        | None -> Array.empty
      
      ///Lookup all edges connected to the vertex v in the graph, returning a Some value if a binding exists and None if not.
      member this.TryGetConnectedEdges((v:'Vertex)) =
         (Dictionary.tryGetValue v vertexOutEdges)
  
      ///Lookup all edges connected to the vertex v in the graph, returning an array of connected edges.
      member this.GetConnectedEdges((v:'Vertex)) =
          match (this.TryGetConnectedEdges(v)) with
              |Some x -> x
              |None   -> [||]
  
      ///Lookup all edges that target the vertex v in the graph, returning a Some value if a binding exists and None if not.
      member this.TryGetInEdges((v:'Vertex)) =
          let tryGetSource = (Dictionary.tryGetValue v vertexOutEdges)
          
  