Re: [Boost-bugs] [Boost C++ Libraries] #2649: iterator_range's assignment fires an assert when rhs is singular

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #2649: iterator_range's assignment fires an assert when rhs is singular
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-04-10 15:06:20

#2649: iterator_range's assignment fires an assert when rhs is singular
---------------------------------------+------------------------------------
  Reporter:  eyal.farago@…             |       Owner:  neilgroves    
      Type:  Bugs                      |      Status:  closed        
 Milestone:  Boost 1.38.0              |   Component:  range         
   Version:  Boost 1.36.0              |    Severity:  Regression    
Resolution:  fixed                     |    Keywords:  iterator_range
---------------------------------------+------------------------------------
Changes (by neilgroves):

  * status:  assigned => closed
  * resolution:  => fixed

Comment:

 The submitted code should never have compiled since
 iterator_range<std::string> is illegal.

 The newly merged RangeEx into Range runs the following code without
 assertion in debug, or crash in release.

 I made the decision to remove the singularity concept from Boost.Range
 entirely. It is my opinion that singularity is a property of iterators and
 that it is not possible to usefully augment range to provide additional
 safety without removing the capability to support valid use-cases.

 #include <string>
 #include <boost/range/iterator.hpp>
 #include <boost/range/sub_range.hpp>

 typedef boost::sub_range<std::string> str_range_t;

 int main(int argc, const char* argv[])
 {
     std::string eyal("eyal");
     str_range_t eyal_range( eyal ), empty_range;

     eyal_range = empty_range;

     return 0;
 }

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/2649#comment:2>
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