In .NET the BinarySearch algorithm (in Lists, Arrays, etc.) appears to fail if the items you are trying to search inherit from an IComparable instead of implementing it directly:
List<B> foo = new List<B>(); // B inherits from A, which implements IComparable<A>
foo.Add(new B());
foo.BinarySearch(new B()); // InvalidOperationException, "Failed to compare two elements in the array."
Where:
public abstract class A : IComparable<A>
{
public int x;
public int CompareTo(A other)
{
return x.CompareTo(other.x);
}
}
public class B : A {}
Is there a way around this? Implementing CompareTo(B other) in class B doesn't seem to work.