Re: [Boost-bugs] [Boost C++ Libraries] #7063: try_unhex() that doesn't throw on bad input

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #7063: try_unhex() that doesn't throw on bad input
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-09-24 16:59:47

#7063: try_unhex() that doesn't throw on bad input
-------------------------------------------------------+--------------------
  Reporter:  Olaf van der Spek <olafvdspek@…>          |       Owner:  marshall 
      Type:  Feature Requests                          |      Status:  new      
 Milestone:  To Be Determined                          |   Component:  algorithm
   Version:  Boost 1.51.0                              |    Severity:  Problem  
Resolution:                                            |    Keywords:           
-------------------------------------------------------+--------------------

Comment (by marshall):

 Something like this?

 Of course, it will still throw if a memory allocation fails. Or the output
 iterator throws. Or the input iterator throws. Or one of the assignments
 throw.

 {{{
    template <typename InputIter, typename OutputIter>
    bool try_unhex ( InputIter first, InputIter last, OutputIter out ) {
       try {
          (void) unhex ( first, last, out );
          return true;
          }
       catch ( const hex_decode_error & ) {}
       return false;
       }
 }}}

 Note:
 * if you pass the output iterator by value, then you lose any changes that
 are made.
 * If you pass the output iterator by reference, then you can't use an
 unnamed temporary (such as the result of `std::back_inserter`)

 In any case, I'm not convinced that this is a good idea.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7063#comment:3>
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