Re: [Boost-bugs] [Boost C++ Libraries] #12136: Propose lexical_cast type traits

Subject: Re: [Boost-bugs] [Boost C++ Libraries] #12136: Propose lexical_cast type traits
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2016-04-19 05:40:14

#12136: Propose lexical_cast type traits
-------------------------------------+-------------------------------------
  Reporter:  Tony Lewis              |      Owner:  apolukhin
  <tonyelewis@…>                     |     Status:  new
      Type:  Feature Requests        |  Component:  lexical_cast
 Milestone:  To Be Determined        |   Severity:  Optimization
   Version:  Boost 1.61.0            |   Keywords:
Resolution:                          |  lexical_cast,trait,ostreamable,istreamable,lexical_castable
-------------------------------------+-------------------------------------

Comment (by apolukhin):

 LexicalCast requires default construction and istreamable/ostreamable from
 operator:
 {{{
 template <class T>
 struct is_lcast_istreamable: mpl::bool_<
     (is_default_constructible<T>::value &&
         (boost::has_right_shift<std::basic_istream<wchar_t>, T>::value ||
          boost::has_right_shift<std::basic_istream<char>, T>::value)
     )
 >
 }}}

 You can make the `is_lcast_ostreamable` similarly. Or you could just use
 the [http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2015/n4436.pdf

 detection idiom].


 Anyway, such trait seems to have limited usage. I'd rather not add it and
 keep the interface of the LexicalCast library as simple as possible.

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/12136#comment:1>
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