[Boost-bugs] [Boost C++ Libraries] #4427: for_each does not take a non-const Function object

Subject: [Boost-bugs] [Boost C++ Libraries] #4427: for_each does not take a non-const Function object
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-07-12 16:18:45

#4427: for_each does not take a non-const Function object
-------------------------------+--------------------------------------------
 Reporter:  chetant@…          |       Owner:  djowel 
     Type:  Bugs               |      Status:  new    
Milestone:  Boost 1.44.0       |   Component:  fusion 
  Version:  Boost 1.43.0       |    Severity:  Problem
 Keywords:  for_each           |  
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 I'm trying to create a type of deserializer, templated by fusion types. I
 have a function object that I initialize with an input stream and its
 templatized operator() takes a record out of that stream and assigns it to
 a given input type.

 I was trying to use fusion::foreach for this:


 {{{
 FusionType fvar;
 EntryReader er(stream);
 // This should call er for each entry in fvar
 for_each(fvar, er);

 }}}

 The problem is that for_each only accepts const references to Function
 objects, so EntryReader::operator()(T& out) cannot read from the stream.
 Is it possible to make the Function reference in for_each non-const?

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4427>
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