[This post is part of a series, "wish-list for future versions of VB"]

IDEA: Flexibility with implementing properties. Allow you to implement a property with more accessors than was specified in the interface your implementing, or the abstract class you're inheriting from.

SCENARIO: An interface declares a readonly property, but you want to implement it with a private setter:

Interface I

    ReadOnly Property p As Integer

End Interface

 

Class C

    Implements I

    Private _p As Integer

 

    Public Property p As Integer Implements I.p

        Get

            Return _p

        End Get

        Private Set(ByVal value As Integer)

            _p = value

        End Set

    End Property

End Class

SCENARIO: One interface has a readonly property, and another has a writeonly property, and you want to implement them both at the same time.

Interface IProducer(Of Out T)

    ReadOnly Property p() As T

End Interface

 

Interface IConsumer(Of In T)

    WriteOnly Property p() As T

End Interface

 

Class C(Of T)

    Implements IProducer(Of T)

    Implements IConsumer(Of T)

    Private _p As T

 

    Public ReadOnly Property p As T Implements IProducer(Of T).p, IConsumer(Of T).p

        Get

            Return _p

        End Get

        Set(ByVal value As T)

            _p = value

        End Set

    End Property

End Class

 

Bill Sheldon suggested that maybe the "Implements" clause in the first scenario should go on the Getter or Setter that it's appropriate to.

 

Provisional evaluation from VB team: This is a decent idea, one that we should consider against all the other decent ideas.