> -----Original Message-----
> From: Peter Dimov [mailto:[EMAIL PROTECTED]
> Sent: Wednesday, June 18, 2003 6:43 AM
> To: Boost mailing list
> Subject: Re: [boost] test_tools_test Metrowerks failure
>
>
> Gennadiy Rozental wrote:
> > Hi,
> >
> > I am having problems with subject test with Metrowerks
> compiler. I was
> > able to minimize the issue to the following snippet: #include <list>
> > #include <iostream>
> >
> > template<typename T>
> > inline void
> > print( std::ostream& ostr, T const& t, long ) { ostr << t; }
> >
> > template<typename T>
> > inline void
> > moo( std::ostream& ostr, T const& t ) { print( ostr, t, 0 ); }
> >
> > inline void
> > print( std::ostream& ostr, std::list<int> const& t, int ) {}
> >
> > void foo()
> > {
> > std::list<int> lst;
> >
> > print( std::cout, lst, 0 ); //1
> > moo( std::cout, lst ); //2
> > }
> >
> > Line 1 compile successfully, while line 2 chokes.
> >
> > Any Ideas?
>
> Yes, the code is broken. moo doesn't see the second overload.
> Templates do argument-dependent lookup from the point of
> instantiation, and since the only namespace associated with
> the 'print(ostr, t, 0)' call is 'std', the second print is
> not found.
All above symbols in fact are in a some namespace. It does not have a
difference (if that what you mean)
> You need to move it before the definition of moo
> (or place it in std:: which is oddly evil but right.)
No. this wouldn't work for me.
In fact I found the solution (I think):
#include <list>
#include <iostream>
/////////////////////////////////////////////
// Library code
template<typename T>
struct printer {
void
operator()( std::ostream& ostr, T const& t )
{ ostr << t; }
};
template<typename T>
inline void
moo( std::ostream& ostr, T const& t ) { printer<T>()( ostr, t ); }
/////////////////////////////////////////////
// Users specialization
template<>
struct printer<std::list<int> > {
void
operator()( std::ostream& ostr, std::list<int> const& t )
{}
};
/////////////////////////////////////////////
// Usage code
void foo()
{
std::list<int> lst;
moo( std::cout, lst ); //2
}
Above works with online Cameau. Seems strange that PS and overloading works
different.
Gennadiy.
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