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: 2014-03-11 23:03:27

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

 I don't see why such a fix is necessary. Wouldn't this work?
 {{{
 template <typename T>
 struct is_nullary<custom_terminal<even_more_custom<T> > : ...
 }}}

 This wouldn't break any exisiting code.

 FWIW, The dummy parameter only has the side effect of being able to be
 used with SFINAE. The main intention was to get rid of some uneeded
 template instatiations.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/7730#comment:22>
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