// CS0457: Ambiguous user defined operators `D.implicit operator D(System.Action)' and `D.explicit operator D(Foo)' when converting from `method group' to `D' // Line: 25 using System; public delegate void Foo (); class D { public static implicit operator D (Action d) { return new D (); } public static explicit operator D (Foo d) { return new D (); } } class Program { static void Main() { D d = (D) Main; } }