Type expected
A type specifier is expected.
The following sample generates CS1031:
namespace x { public class ii { } public class a { public static operator +(a aa) { // CS1031 // the following line resolves CS1031 // public static ii operator +(a aa) return new ii(); } public static void Main() { e = new base; // CS1031, not a type e = new this; // CS1031, not a type e = new (); // CS1031, not a type } } }