id,summary,reporter,owner,description,type,status,milestone,component,version,severity,resolution,keywords,cc
6357,Resolve ambiguity for unqualified call to begin/end,Thomas Heller,Thomas Heller,"On 12/16/2011 10:44 AM, Nathan Ridge wrote:
> 
> Hello,
> 
> I am running into a problem where an unqualified call to begin()
> on a range type whose template parameters include a Boost.Phoenix
> type (for examle filtered_range<Pred, R>  where Pred is a phoenix
> function) is ambiguous because, in addition to the intended
> std::begin, phoenix::begin is being found by ADL.
> 
> What can be done about this? There exists precedent for placing
> boost::xxx::begin/end functions in ADL barrier namespaces because
> C++11 encourages unqualified calls to begin/end (specifically,
> this was done for boost::range::begin/end). Should the same thing
> be done for Phoenix?
> 
> Here is a minimal example that reproduces the problem:

{{{
#include<iterator>

#include<boost/range/adaptor/filtered.hpp>
#include<boost/phoenix/phoenix.hpp>

using std::begin;

{{{
int main()
{
     using boost::phoenix::arg_names::arg1;
     using boost::adaptors::filtered;
    
     int v[5];
     const auto&  f = v | filtered(arg1<  0);
     begin(f);
}
}}}",Bugs,closed,To Be Determined,phoenix,Boost 1.48.0,Problem,fixed,,