template<class T>
struct A: public T {
        // считается что some_func_in_T() находится в T
    void f() {
                 some_func_in_T<T>();
    }
};

mingw32-g++.exe       -I"C:\Program Files\Microsoft DirectX 9.0 SDK (April 2005)\Include" -I"C:\Program Files\msys\include" -I"C:\Program Files\msys\include\c++\3.4.4" -c main.cpp -o main.o
main.cpp: In member function `void A<T>::f()':
main.cpp:7: error: `some_func_in_T' undeclared (first use this function)
main.cpp:7: error: (Each undeclared identifier is reported only once for each function it appears in.)
main.cpp:7: error: expected primary-expression before '>' token
main.cpp:7: error: expected primary-expression before ')' token

template<class T>
struct A: public T 
{
    void f() 
    {
                 this->some_func_in_T<T>();
    }
};

АШ>template<class T>
АШ>struct A: public T 
АШ>{
АШ>    void f() 
АШ>    {
АШ>                 this->some_func_in_T<T>();
АШ>    }
АШ>};
АШ>

main.cpp:8: error: expected primary-expression before '>' token
main.cpp:8: error: expected primary-expression before ')' token

template<class T,class P>
struct A: public T 
{
    void f() 
    {
        T::template some_func_in_T<T>();

        // или

        this->template some_func_in_T<T>();
    }
};

sch>template<class T>
sch>struct A: public T {
sch>        // считается что some_func_in_T() находится в T
sch>    void f() {
sch>                 some_func_in_T<T>();
sch>    }
sch>};
sch>

void f() {
  this->template some_func_in_T<T>();
}

АШ>>template<class T>
АШ>>struct A: public T 
АШ>>{
АШ>>    void f() 
АШ>>    {
АШ>>                 this->some_func_in_T<T>();
АШ>>    }
АШ>>};
АШ>>

sch>main.cpp:8: error: expected primary-expression before '>' token
sch>main.cpp:8: error: expected primary-expression before ')' token
sch>

template<class T>
struct A: public T 
{
    void f() 
   {
                 this->template some_func_in_T<T>();
    }
};

template <class T>
struct _
{
    void f() { Chto hochu, to i pishu. Vot. I ne fig parsit eto }
};

template<class T> 
typename boost::disable_if<boost::is_pointer<T>::value, void>::type
f()
{
}