Re: [boost] Re: Status of Boost.Python docs?

From: Jonathan Wakely (cow_at_[hidden])
Date: 2004-10-05 11:11:10

On Tue, Oct 05, 2004 at 10:40:43AM -0400, David Abrahams wrote:

> > OK, it was no problem to fix this. But if run on the complete
> > operators example, the compiler (gcc 3.4.2 on 686-pc-linux-gnu) chokes
> > nevertheless. And this time I can't make much sense out of the error
> > messages. 
> 
> > (In case someone is interested, the compiler output is
> > online at <URL:http://tinyurl.com/5u3rr>.)
> 
> error: ambiguous overload for 'operator+' in 'l + r'
> note: candidates are: operator+(long int, long int) <built-in>
> note:                 number boost::operator+(const number&, const number&)
> 
> GCC claims that the operator+ provided by integer_arithmetic<number>
> is ambiguous with the one that uses an implicit conversion to int
> on each side of the operator.  That's a compiler bug; the former is
> an exact match.

Are you sure?
(I don't doubt you are, just trying to understand it myself :)

Looks to me as though the exact match would be

    operator+(number&, long int const&);

So either of the overloads given would involve a conversion.

So any bug wouldn't in the overload resolution, but in whatever caused
boost::python::detail::operator_l<op_add>::apply<L, R>::execute(L&, const R&)
to be instantiated ... [with L = number, R = long int]

Should there be another overload that doesn't require the conversion?

jon

-- 
"Entropy requires no maintenance"