Compiler Error C3920


For the latest documentation on Visual Studio 2017 RC, see Visual Studio 2017 RC Documentation.

'operator'' : cannot define a postfix increment/decrement WinRT or CLR operator Calling the postfix WinRT or CLR operator will call the corresponding prefix WinRT or CLR operator (op_Increment/op_Decrement), but with postfix semantics

The Windows Runtime and CLR do not support the postfix operator and user-defined postfix operators are not allowed. You can define a prefix operator and the prefix operator will be used for both pre- and post-increment operations.

The following sample generates C3920 and shows how to fix it:

// C3920.cpp  
// compile with: /clr /LD  
public value struct V {  
   static V operator ++(V me, int)  
   // try the following line instead  
   // static V operator ++(V me)  
   {   // C3920  
      return me;  
   int m_i;