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From: ruben safir <ruben@mrbrklyn.com>
Newsgroups: comp.lang.c++
Subject: base_ostream template arguments
Date: Mon, 13 Jun 2011 04:40:57 +0000 (UTC)
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Xref: x330-a1.tempe.blueboxinc.net comp.lang.c++:6671

The base_ostream template is defined as follows (according to Struostrup)


template<class Ch, class Tr = char_traits<Ch> >
class std::basic_ostream : virtual public basic_ios<Ch, Tr > {
public:
	virtual ~basic_ostream();
//...
};


since Tr is always defined as a function of Ch, why was it necessary for 
two template parameters?

Ruben