// CS0121: The call is ambiguous between the following methods or properties: `IList.Count()' and `ICounter.Count()' // Line: 29 using System; interface IList { int Count (); } interface ICounter { int Count (); } interface ICollection { int Count { set; } } interface IListCounter: IList, ICounter, ICollection { } class Test { static void Foo (IListCounter t) { t.Count (); } }