nodo para lista doblemente enlazada

' Gambas class file

Private hdato As String
Property dato As String

Private hsiguiente As Nodo
Property siguiente As Nodo

Private hprevio As Nodo
Property previo As Nodo

Public Sub _new(dat As String, Optional prox As Nodo)

  hdato = dat
  hsiguiente = prox

End

Private Function dato_Read() As String

  Return hdato

End

Private Sub dato_Write(Value As String)

  hdato = Value

End

Private Function siguiente_Read() As Nodo

  Return hsiguiente

End

Public Function VerLista() As String

  Dim frutas As String
  Dim un_nodo As Nodo

  un_nodo = Me
  While True
    un_nodo = un_nodo.siguiente
    If IsNull(un_nodo) Then
      Break
    Endif

    frutas &= un_nodo.dato & "<br>"

  Wend

  Return frutas

End

Private Sub siguiente_Write(Value As Nodo)

  hsiguiente = Value

End

Private Function previo_Read() As Nodo

  Return hprevio

End

Private Sub previo_Write(Value As Nodo)

  hprevio = Value

End