BUG: IntelliSense Limitations with Templates

• Microsoft Visual C++, 32-bit Editions, version 6.0

SYMPTOMS

This article focuses on the limitations of IntelliSense when working with templates.

• IntelliSense does not recognize template member functions defined outside of the template class.
  
  When a template member function is defined outside of the template class, it does not appear in an instantiated template object's Member list, and does not provide Parameter and Type Info. It also does not appear in the ClassView pane. With Visual C++ 6.0, the only way to have IntelliSense work correctly with template member functions is to define all member functions inside of the template class declaration.
• Coding inside of nonclass template functions does not fully utilize IntelliSense.
  
  IntelliSense does not parse the bodies of template functions that are not member functions of a class. As a result, most IntelliSense features do not work inside of a template function definition.
• Template class specializations are not properly interpreted by IntelliSense.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article. We are researching this bug and will post new information here in the Microsoft Knowledge Base as it becomes available.

MORE INFORMATION

Consider the following code sample. Comments that are examples are marked with \\EXAMPLE. The code directly below needs to be uncommented in order to reproduce the problem. The comments following the code explain the problem:

Sample Code

   //Test.cpp
   #include <stdio.h>

   // A Template Class
   // 
   template <class T, int i>
   class TempClass
   {
   public:
       TempClass(void){}
       ~TempClass(void){}
       int MemberSet(T a, int b);
       int GetSize()
       {
   return arraysize;
       }
   private:
       T Tarray[i];
       int arraysize;
   };

   // A Simple Class
   // 
   class TestClass
   {
   public:
      TestClass(void){}
      ~TestClass(void){}
      int m;
      int n;
   };

   // Template Member Function Defined outside of the template class
   // 
   template <class T, int i>
   int TempClass<T, i>::MemberSet(T a, int b)
   {
      if( ( b >= 0 ) && (b < i) )
      {
        Tarray[b++] = a;
        return sizeof( a );
      }
      else
        return -1;
   };

   // Template Class
   // 
   template <class T>
   class Print
   {
   public:
      // Declare an instance of TestClass
      TestClass te;

      // EXAMPLE
      //te.
      // #2 No members displayed
      // all types but char

      void f(int, double)
      {
         printf("Print<T>\n");
      }
   };

   // Specialization of Print<class T>
   // 
   template <>
   class Print<char>
   {
   public:
      // just for chars
      void f(char*)
      {
         printf("Print<char>\n");
      }
   };

   void main()
   {
   TempClass<char,10> t;

   // EXAMPLE
   //t.
   // #1 MemberSet is absent from the member list
   // MemberSet does not appear in the ClassView pane
   // Define MemberSet in the TempClass declaration
   // to correct this problem

   Print<char> pc;

   // EXAMPLE
   //pc.f(
   // #3
   // pc.f  Tool tip shows all types but char
   // pc.f( Parameter list is int, double
   } 

REFERENCES

For additional information, please see the following article in the Microsoft Knowledge Base:

Q153284 Limitations of IntelliSense in Visual C++ 6.0

Additional query words: kbvc600bug

Keywords : kbVC600bug
Version : WINNT:6.0
Platform : winnt
Issue type : kbbug