Re: [Boost-bugs] [Boost C++ Libraries] #7730: Generic specializations of is_nullary for custom terminals are not possible

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #7730: Generic specializations of is_nullary for custom terminals are not possible
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2014-02-22 09:15:52

#7730: Generic specializations of is_nullary for custom terminals are not possible
-------------------------------+---------------------
  Reporter:  andysem           |      Owner:  theller
      Type:  Bugs              |     Status:  new
 Milestone:  To Be Determined  |  Component:  phoenix
   Version:  Boost 1.52.0      |   Severity:  Problem
Resolution:                    |   Keywords:
-------------------------------+---------------------

Comment (by John Fletcher <J.P.Fletcher@…>):

 The typedef is provided in the default custom_terminal - see the code
 below from
 {{{
 boost/phoenix/core/terminal.hpp
 }}}

 {{{
     template <typename T, typename Dummy>
     struct custom_terminal
 #ifndef BOOST_PHOENIX_NO_SPECIALIZE_CUSTOM_TERMINAL
     {
       typedef void _is_default_custom_terminal; // fix for #7730
     }
 #endif
       ;
 }}}

 The problem arises when people developing their own terminal specialize
 the custom terminal. The case which was made in this bug report was for
 them to have the freedom I have now given. It has needed a fix in the case
 of Boost Spirit. I have now included a check on the spirit headers in the
 testing of phoenix, to pick up anything similar before it even gets into
 develop.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7730#comment:12>
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