The new C++/CLI syntax in VC++ 2005

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Using a newer C++ compiler build than the one in VC++ 2005 Beta 1, I wanted to try what Stan described on String Literals are now a Trivial Conversion to String and a couple of other new features:

 

using namespace System ;

using namespace stdcli::language ;

public ref class B

{

   public:

      B() { Console::WriteLine( "B::B()" ) ; }

      ~B() { Console::WriteLine( "B::~B() a.k.a. Dispose()" ) ; }

   protected:

      !B() { Console::WriteLine( "B::!B() a.k.a. Finalize()" ) ; }

} ;

public ref class R1 : B

{

   public:

      R1( short ) { Console::WriteLine( "R1::R1()" ) ; }

      ~R1() { Console::WriteLine( "R1::~R1() a.k.a. Dispose()" ) ; }

      void f( const char * ) { Console::WriteLine( "f( const char * )" ) ; }

      void f( const wchar_t * ) { Console::WriteLine( "f( const wchar_t * )" ) ; }

      void f( String ^ ) { Console::WriteLine( "f( String ^ )" ) ; }

   protected:

      !R1() { Console::WriteLine( "R1::!R1() a.k.a. Finalize()" ) ; }

} ;

public ref class R2 : B

{

   public:

      R2( short ) { Console::WriteLine( "R2::R2()" ) ; }

   protected:

      !R2() { Console::WriteLine( "R2::!R2() a.k.a. Finalize()" ) ; }

} ;

void wmain()

{

   R1 r1(32767) ;

   R2 r2(-32768) ;

   r1.f( "ANSI" ) ;

   r1.f( static_cast<const char *>("ANSI") ) ;

   r1.f( L"Unicode" ) ;

   r1.f( static_cast<const wchar_t *>(L"Unicode") ) ;

}

 

 

The output is:

 

B::B()

R1::R1()

B::B()

R2::R2()

f( String ^ )

f( const char * )

f( String ^ )

f( const wchar_t * )

B::~B() a.k.a. Dispose()

R1::~R1() a.k.a. Dispose()

B::~B() a.k.a. Dispose()

Note that R2::!R2() is not called as System.GC::SuppressFinalize() was called in B::~B(): I would have liked to see a warning when compiling the source.

Something like:

B, the base class for R2 has a destructor (Dispose()) and R2 does not: R2:!R2() (R2::Finalize()) might not be called.

 

Why might? Here is the output I got by adding System::Environment::Exit(0) as the last line in wmain():

B::B()

R1::R1()

B::B()

R2::R2()

f( String ^ )

f( const char * )

f( String ^ )

f( const wchar_t * )

R2::!R2() a.k.a. Finalize()

B::!B() a.k.a. Finalize()

R1::!R1() a.k.a. Finalize()

B::!B() a.k.a. Finalize()