[Boost-bugs] [Boost C++ Libraries] #8846: Improvements to Spirit Qi Qt QString custom_string.cpp example

Subject: [Boost-bugs] [Boost C++ Libraries] #8846: Improvements to Spirit Qi Qt QString custom_string.cpp example
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2013-07-18 08:45:11

#8846: Improvements to Spirit Qi Qt QString custom_string.cpp example
-------------------------------------+--------------------------
 Reporter:  mloskot                  |      Owner:  djowel
     Type:  Patches                  |     Status:  new
Milestone:  To Be Determined         |  Component:  spirit
  Version:  Boost Development Trunk  |   Severity:  Optimization
 Keywords:  spirit qi qt qstring     |
-------------------------------------+--------------------------
 Tim Angus asked me to submit this patch (Boost Trac was complaining for
 him with "Submission rejected as potential spam").


 There is an example of how to use Qi with a custom string (in this case a
 QString from the Qt framework). This is very helpful but it doesn't work
 in conjunction with the debug facilities. The following patch fixes this
 by adding a couple of template specialisations.

 Patch:
 {{{
 Index: libs/spirit/example/qi/custom_string.cpp
 ===================================================================
 --- libs/spirit/example/qi/custom_string.cpp    (revision 85071)
 +++ libs/spirit/example/qi/custom_string.cpp    (working copy)
 @@ -34,6 +34,26 @@
              return true;
          }
      };
 +
 +    // Test if a QString is empty (required for debug)
 +    template <>
 +    struct is_empty_container<QString>
 +    {
 +        static bool call(QString const& c)
 +        {
 +            return c.isEmpty();
 +        }
 +    };
 +
 +    // Define how to stream a QString (required for debug)
 +    template <typename Out, typename Enable>
 +    struct print_attribute_debug<Out, QString, Enable>
 +    {
 +        static void call(Out& out, QString const& val)
 +        {
 +            out << val.toStdString();
 +        }
 +    };
 }}}

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/8846>
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