Q139458: FIX: Ambiguous C2966 Error with Nested Template Classes

Article: Q139458
Product(s): Microsoft C Compiler
Version(s): 
Operating System(s): 
Keyword(s): kbLangCPP kbVC kbVC500fix
Last Modified: 30-JUL-2001

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The information in this article applies to:

- The Compiler included with Microsoft Visual C++, 32-bit Edition 
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SYMPTOMS
========

An ambiguous C2966 error is generated if any members of a nested template class
are defined externally. The sample code shown in the "More Information" section
of this article reproduces this problem and gives the following error message:

  error C2966: '<Unknown>' : adding member function of same name as
  existing static data member for template class 'Outer'

RESOLUTION
==========

Define members of a nested template class inline only.

NOTE: external definitions with the inline keyword will still generate the
ambiguous C2966 error.

STATUS
======

Microsoft has confirmed this to be a bug in the Microsoft products listed at the
beginning of this article. This bug was corrected in Visual C++ version 5.0.

MORE INFORMATION
================

Sample Code to Reproduce Problem
--------------------------------

     // Compile option needed: none

     template<class T> class Outer {
       public:
           class Inner {
           public:
               static T sobj;
               static T smfunc(T arg);
      };

       };

       //Initialize nested class static object

       template <class T> T Outer<T>::Inner::sobj = T();

       // Out-of-line definition of nested class static member function
       // Moving this definition inside class resolves the error
      template <class T> T Outer<T>::Inner::smfunc(T arg)
      {
         return arg + sobj;
      }

Additional query words: kbVC400bug 10.00 10.10 10.20

======================================================================
Keywords          : kbLangCPP kbVC kbVC500fix 
Technology        : kbVCsearch kbAudDeveloper
Version           : :
Issue type        : kbbug
Solution Type     : kbfix

=============================================================================

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