On 08-11-2012 11:11, Olaf van der Spek wrote:

On Thu, Nov 8, 2012 at 9:35 AM, Gennadiy Rozental <rogeeff@gmail.com> wrote:

...

Hi,

iterator_range operators are defined like this:

template< class IteratorT, class ForwardRange > inline bool operator==( const ForwardRange& l, const iterator_range<IteratorT>& r ) { return boost::equal( l, r ); }

These needs to be restricted with enable_if on type of first argument. I have a scenario where I want to define operator== for my own type and want to be able to use it with iterator_range as second argument. Above definition makes it impossible.

Is this related to https://svn.boost.org/trac/boost/ticket/6715? Sadly not a single response from the Range maintainers.

It seems to be related. What would the enable_if expression look like? -Thorsten

On Thu, Nov 8, 2012 at 4:48 AM, Mathias Gaunard < mathias.gaunard@ens-lyon.org> wrote:

On 08/11/12 13:12, Thorsten Ottosen wrote:

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On 08-11-2012 11:11, Olaf van der Spek wrote:

...

On Thu, Nov 8, 2012 at 9:35 AM, Gennadiy Rozental <rogeeff@gmail.com> wrote: Is this related to https://svn.boost.org/trac/**boost/ticket/6715<https://svn.boost.org/trac/boost/ticket/6715> ? Sadly not a single response from the Range maintainers.

It seems to be related.

What would the enable_if expression look like?

Replacing all overalods of operator== by something like

template<class A0, class A1> typename enable_if< mpl::or_< is_base_of<iterator_range_**base, A0>, is_base_of<iterator_range_**base, A1> > , bool

...

::type operator==(A0 const& a0, A1 const& a1) { return boost::equal(a0, a1); }

should allow to fix the bug above.

Though an improvement, that's still not very constrained and I doubt it will address Gennadiy's issue. - Jeff

On 8 Nov 2012 10:13, "Olaf van der Spek" <ml@vdspek.org> wrote:

On Thu, Nov 8, 2012 at 9:35 AM, Gennadiy Rozental <rogeeff@gmail.com>

wrote:

...

Hi,

iterator_range operators are defined like this:

template< class IteratorT, class ForwardRange > inline bool operator==( const ForwardRange& l, const iterator_range<IteratorT>& r ) { return boost::equal( l, r ); }

These needs to be restricted with enable_if on type of first argument. I have a scenario where I want to define operator== for my own type and want to be able to use it with iterator_range as second argument. Above definition makes it impossible.

Is this related to https://svn.boost.org/trac/boost/ticket/6715? Sadly not a single response from the Range maintainers.

Sadly the maintainer has been extremely busy. I have acknowledged that tickets have been waiting longer than I would have liked. It is something I will address but has never appeared to be anything more than a minor inconvenience previously. In the new year I will be able to devote more time to improving Boost.Range. this will include bringing in new code submitted by others that I have been reviewing for a little while. I am listening to people and ensuring that anything major is addressed. I am also working toward a schedule that will deliver more for Boost. I am also disappointed by the amount of time that I have had available for this. The tickets for Boost.Range are not being ignored and there is a credible plan to hasten progress.

-- Olaf

Neil Groves

On 26-11-2012 19:36, Olaf van der Spek wrote:

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The tickets for Boost.Range are not being ignored and there is a credible plan to hasten progress.

Hi Neil,

What can we do to help you?

I don't know the procedure for this, but I would like to see more people being able to apply patches we basically all agree should be done. -Thorsten

On Thu, Nov 8, 2012 at 2:17 PM, Gennadiy Rozental <rogeeff@gmail.com> wrote:

Jeffrey Lee Hellrung, Jr. <jeffrey.hellrung <at> gmail.com> writes:

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Is your type a range?

No.

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How does its semantics differ from the operator== above?

I am building an expression template structure to delay operator== evaluation.

Sounds like hackery :)

...

Presumably if you want to specifically address boost::iterator_range, then

template< class I > inline bool operator==(my_type, iterator_range<I>);

should be a preferable overload.

Unfortunately it is not. I am getting ambiguity errors.

Works for me (MSVC9): #include <boost/range/iterator_range.hpp> struct my_type { }; template< class I > inline bool operator==(my_type, boost::iterator_range<I>) { return false; } int main(int argc, char* argv[]) { my_type x; boost::iterator_range< int* > i; x == i; return 0; } - Jeff