Re: [Boost-bugs] [Boost C++ Libraries] #3298: Iterating over a map fails to compile with MSVC 9 (works with CYGWIN GCC 4.3.2)

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #3298: Iterating over a map fails to compile with MSVC 9 (works with CYGWIN GCC 4.3.2)
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2009-07-29 14:09:09

#3298: Iterating over a map fails to compile with MSVC 9 (works with CYGWIN GCC
4.3.2)
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 Reporter:  Marshall Galbraith <Marshall.Galbraith@…>          |       Owner:  agurtovoy  
     Type:  Bugs                                               |      Status:  new        
Milestone:  Boost 1.40.0                                       |   Component:  mpl        
  Version:  Boost 1.39.0                                       |    Severity:  Showstopper
 Keywords:  map                                                |  
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Comment(by Marshall Galbraith):

 First I want to acknowledge that I am an MPL novice, and am still learning
 the ropes of this extremely useful library. I have attached an updated
 example of the problem. This implementation takes better advantage of the
 tools provided in the mpl library.

 I have two template meta functions defined in this example which joins two
 maps, MapL and MapR. The first function, join_maps_1, generates a new copy
 of the joint maps using copy and joint_view. If I understand things
 correctly, this requires size<MapL> + size<MapR> instantiations. This
 version seems to work without problems.

 The second function, join_maps_2, inserts MapR into MapL using copy<>. It
 should require size<MapL> instantiations. However, if the resulting map is
 passed to for_each<>, the code fails to compile with MSVC 9 if a key has
 been erase from MapL.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/3298#comment:1>
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