Re: [Boost-bugs] [Boost C++ Libraries] #5490: Fusion fails to insulate user-supplied template parameters from unintentional MPL placeholder substitution (?)

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #5490: Fusion fails to insulate user-supplied template parameters from unintentional MPL placeholder substitution (?)
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2015-08-29 16:23:01

#5490: Fusion fails to insulate user-supplied template parameters from
unintentional MPL placeholder substitution (?)
-------------------------------------+-------------------------------------
  Reporter:  Jeffrey Hellrung        |      Owner:  djowel
  <jeffrey.hellrung@…>               |     Status:  new
      Type:  Bugs                    |  Component:  fusion
 Milestone:  To Be Determined        |   Severity:  Problem
   Version:  Boost 1.47.0            |   Keywords:  fusion, mpl,
Resolution:                          |  placeholder, substitution
-------------------------------------+-------------------------------------

Comment (by Kohei Takahashi <flast@…>):

 Does the quoted version (i.e. "2") work as you intended? It instantiate
 `foo<quote1<is_integral>>` but not `foo<true_>` or `foo<false_>` because
 `foo<is_integral<_1>>` and `quote1<is_integral>` are lambda expression,
 but `foo<quote1<is_integral>>` is not.

 see: http://melpon.org/wandbox/permlink/5rAG4sqeTJPcqtDe

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/5490#comment:1>
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