Hi,

I have a template class, it is defined in file_a.cpp.  It is a waste of time
as the lines of codes in file_a.cpp is growing.  So I am considering to move
some of the mature functions to file_b.cpp to lower the compiler burden.
Then the problems came.

=============
file_a.cpp

#includes in file_a.cpp

MyTemplate<Class T> MyInstance;        // declaration of instance
......
============
file_b.cpp
......
#includes in file_a.cpp
extern MyTemplate<Class T> MyInstance;
......

the compiler gave me that already MyInstance is defined in file_a.obj
If I remove extern MyTemplate<Class T> MyInstance;  from file_b.cpp, the
compiler will give 'MyInstance'  undeclared identifier.  For variables, I
know it is the
correct way to use extern.  what is wrong here?

Thanks,

robin




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