id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
514,lexical_cast & pure virtual functions & VC 8 STL,sergey_shandar,alnsn,"{{{
VC 8.0 can't compile the valid code:
===== =====
#include <boost/lexical_cast.hpp>

class A 
{
public:
	virtual void out(std::ostream &) const = 0;
};

class B: public A
{
public:
	virtual void out(std::ostream &O) const { O << ""B""; }
};

std::ostream &operator<<(std::ostream &O, const A &a)
{
	a.out(O);
	return O;
};

int main()
{
	const A &a = B();
	boost::lexical_cast<std::string>(a);
	return 0;
}
===== =====

The problem occurs in VC STL:
===== =====
c:\program files\microsoft visual studio
8\vc\include\limits(102) : error C2259: 'A' : cannot
instantiate abstract class
===== =====
However, should boost::lexical_cast use
std::numeric_cast in this case?

}}}",Bugs,closed,,None,None,,Fixed,,