inner class in template class

[Martin v. Loewis]

> is it a correct code or just the compilers can understand me ?:

Thanks for your bug report. At least, I suppose this is a bug report;
if it is a question on C++, please ask that again in comp.lang.c++.

g++ currently cannot compile your code, as the iostreams library is
not conforming to the standard, yet. In particular, no templates named
basic_ostream or char_traits are defined, which causes the errors you
probably see.

Hope this helps,
Martin