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Does Covariance & Contravariance work in Unity?

Discussion in 'Scripting' started by Deleted User, Mar 8, 2015.

  1. Deleted User

    Deleted User

    Guest

    I have an interface:

    Code (CSharp):
    1. public interface IScrollable<out T> where T : MonoBehaviour
    2. {
    3.         IEnumerable<T> ScrollableItems { get; }
    4. }
    But I'm getting the error: "The covariant type parameter `T' must be invariantly valid on `IScrollable<T>.ScrollableItems'"
     
    Deleted User, Mar 8, 2015
    #1

  2. Limyc

    Limyc

    Joined:
    Jan 27, 2013
    Posts:
    29
    Unfortunately, generic covariance/contravariance was introduced in .Net 4.0. Unity is using a Mono version that equates to .Net 3.5. So until Unity can update Mono, the code listed above will not work.
     
    Limyc, Mar 8, 2015
    #2
    Deleted User likes this.