>>>>> Peter J Brock <peter@magna.com.au> writes:

> The following code illustrates a bug in the implementation of
> templates in MS Visual C++ 4.0.

Yup, looks that way.

[snip]
> So leads one to the question of how will compilers be vetted against a
> standard when it comes?

With testsuites, same as with any other language.  There are already
several commercial C++ testsuite vendors.

Jason
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The following code illustrates a bug in the implementation of
templates in MS Visual C++ 4.0.

//___________begin code sample__________________________
// test.cpp

template <class T>
class VeryTesting
{
 public:
  VeryTesting();
  T& operator()();
  T  m_T;
};

template <class T>
inline
VeryTesting<T>::VeryTesting ()
{
}

template <class T>
inline T&
VeryTesting<T>::operator ()()
{
 return m_T;
}

//  Uncomment this block of code and it all works!
// template VeryTesting<double>;

class A
{
public :
 A(){}
 ~A(){}

 VeryTesting<double>& test(VeryTesting<double>& fdTest)
 {
  fdTest() = 5.0; //error C2064: term does not evaluate to a function
  return fdTest;
 }
};

main()
{
 VeryTesting<double> f;
 f() = 5.0;
 A aObject;
 aObject.test(f);
}
//___________end code sample___________________________


The problem is that VeryTesting<double> is not instantiated correctly
by the MS Visual C++ 4.0 compiler. This results in the error message
that says function fdTest() does not evaluate to a function.

The code compiles under Borland 4.5.

So leads one to the question of how will compilers be vetted against a
standard when it comes?

Cheers,
Peter J Brock http://www.magna.com.au/~peter

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