Re: [Boost-bugs] [Boost C++ Libraries] #4489: References to function object types

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #4489: References to function object types
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2012-06-04 10:43:09

#4489: References to function object types
--------------------------------------+-------------------------------------
  Reporter:  cschmidt                 |       Owner:  djwalker
      Type:  Feature Requests         |      Status:  new     
 Milestone:  Boost 1.44.0             |   Component:  utility 
   Version:  Boost Development Trunk  |    Severity:  Problem 
Resolution:                           |    Keywords:          
--------------------------------------+-------------------------------------

Comment (by michel):

 Boost's decltype-based `result_of` already accepts references to function
 objects.
 Users can explicitly enable decltype-based `result_of` by defining
 `BOOST_RESULT_OF_USE_DECLTYPE`.
 Or, in the trunk code, it is automatically enabled when a compiler
 supports N3276 decltype (e.g. clang-3.1).

 For example, on clang-3.1 with the following functor:
 {{{
 struct F
 {
     short operator()(int) &  { return 0; }
     float operator()(int) && { return 0; }
 };
 }}}
 * `boost::result_of<F& (int)>::type` evaluates to `short`.
 * `boost::result_of<F&&(int)>::type` evaluates to `float`.

 Is this enough for you? Or, do you want this feature in tr1-style
 `result_of`?

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4489#comment:5>
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