Re: [Boost-bugs] [Boost C++ Libraries] #2841: boost::hash to support boost::dynamic_bitset

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #2841: boost::hash to support boost::dynamic_bitset
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2009-03-09 22:36:20

#2841: boost::hash to support boost::dynamic_bitset
----------------------------------+-----------------------------------------
  Reporter:  astukalov_at_[hidden]  |       Owner:  gennaro_prota 
      Type:  Feature Requests     |      Status:  new           
 Milestone:  Boost 1.39.0         |   Component:  dynamic_bitset
   Version:  Boost 1.38.0         |    Severity:  Optimization  
Resolution:                       |    Keywords:                
----------------------------------+-----------------------------------------

Comment(by astukalov_at_[hidden]):

 Replying to [comment:3 danieljames]:
 > '0', '00', '000' and '0000' should have different hash values, but
 unless I've misunderstood dynamic_bitset m_bits will be the same for all
 of them.
 I think so too. It should be true for all zero bitsets with lengths <=
 bits per bitset block. For bigger lengths - two and more values would be
 hash_combined, resulting in different hash key.

 Anyway, not including bitset length into hashing directly would have so
 small performance improvement, that I withdraw my previous comment. :)

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/2841#comment:4>
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