[Boost-bugs] [Boost C++ Libraries] #6282: filter and other views transform the sequence type

Subject: [Boost-bugs] [Boost C++ Libraries] #6282: filter and other views transform the sequence type
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2011-12-16 22:34:45

#6282: filter and other views transform the sequence type
----------------------------------+-----------------------------------------
 Reporter:  ramey                 |       Owner:  jfalcou     
     Type:  Feature Requests      |      Status:  new         
Milestone:  To Be Determined      |   Component:  mpl         
  Version:  Boost Release Branch  |    Severity:  Optimization
 Keywords:                        |  
----------------------------------+-----------------------------------------
 code such as the following doesn't work.  That is, none of the views can
 produce a set type sequence.  Note this is diffferent from fusion so it is
 possible.  I also realize that this is non-trivial enhancement. Oh well.
 {{{
     struct a {};
     struct b {};
     struct c {};
     struct d {};
     typedef boost::mpl::set<a, b, c> s1;
     BOOST_CONCEPT_ASSERT(( boost::mpl::AssociativeSequence<s1> ));
     typedef boost::mpl::set<c, d> s2;
     BOOST_CONCEPT_ASSERT(( boost::mpl::AssociativeSequence<s2> ));
     typedef boost::mpl::joint_view<s1, s2>::type sdiff;
     BOOST_CONCEPT_ASSERT(( boost::mpl::AssociativeSequence<sdiff> ));
 }}}

 I know it's correct as is - that is it works according to they it's
 described in the manual.  But it was hard to find my mistake.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/6282>
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