Re: [Cppcms-users] Compile error: traits is not a template

[陈抒 <csf...@gm...>]

Thank you. But I see new error.
groups.h file:

#ifndef __GROUPS_H
#define __GROUPS_H

#include <vector>
#include <boost/shared_ptr.hpp>
#include "group.h"

namespace kaimei{

  class groups{
  public:
    typedef std::vector<boost::shared_ptr<group> >::iterator iterator;
    typedef std::vector<boost::shared_ptr<group> >::const_iterator
const_iterator;

    void add(boost::shared_ptr<group> g);

    bool empty() const;

    unsigned int size() const;

    std::string json_string() const;

    friend class cppcms::json::traits<kaimei::groups>;

  private:
    std::vector<boost::shared_ptr<kaimei::group> > values_;
  };

}

namespace cppcms {
  namespace json {

    template<>
      struct traits<kaimei::groups> {

      static void set(value &v, kaimei::groups const& in) {
v.set("size", in.size());
 v.set("values", in.values_);
      }
    };

  }
}

#endif


error message:
  3%] Generating ../../src/view/welcome.cpp, ../../src/view/home.cpp,
../../src/view/gprs_message.cpp, ../../src/view/gprs_manager.cpp,
../../src/view/gprs_password.cpp, ../../src/view/gprs_log.cpp,
../../src/view/register_client.cpp, ../../src/view/gprsConfig.cpp,
../../src/view/login.cpp, ../../src/view/group_management.cpp
[  6%] Building CXX object bin/CMakeFiles/cppweb.dir/groups.cpp.o
In file included from /home/chenshu/work/kaimei/cppweb/include/group.h:5:0,
                 from /home/chenshu/work/kaimei/cppweb/include/groups.h:6,
                 from /home/chenshu/work/kaimei/cppweb/src/groups.cpp:1:
/usr/include/cppcms/json.h: In member function ‘void
cppcms::json::value::set_value(const T&) [with T =
boost::shared_ptr<kaimei::group>]’:
/usr/include/cppcms/json.h:604:5:   instantiated from ‘static void
cppcms::json::traits<std::vector<T> >::set(cppcms::json::value&, const
std::vector<T>&) [with T = boost::shared_ptr<kaimei::group>]’
/usr/include/cppcms/json.h:247:4:   instantiated from ‘void
cppcms::json::value::set_value(const T&) [with T =
std::vector<boost::shared_ptr<kaimei::group> >]’
/usr/include/cppcms/json.h:316:4:   instantiated from
‘cppcms::json::value::value(const T&) [with T =
std::vector<boost::shared_ptr<kaimei::group> >]’
/usr/include/cppcms/json.h:352:4:   instantiated from ‘void
cppcms::json::value::set(const char*, const T&) [with T =
std::vector<boost::shared_ptr<kaimei::group> >]’
/home/chenshu/work/kaimei/cppweb/include/groups.h:39:28:   instantiated
from here
/usr/include/cppcms/json.h:247:4: error: incomplete type
‘cppcms::json::traits<boost::shared_ptr<kaimei::group> >’ used in nested
name specifier
make[2]: *** [bin/CMakeFiles/cppweb.dir/groups.cpp.o] Error 1
make[1]: *** [bin/CMakeFiles/cppweb.dir/all] Error 2
make: *** [all] Error 2


陈抒
Best regards
http://blog.csdn.net/sheismylife


On Sat, Sep 1, 2012 at 2:34 PM, Artyom Beilis <art...@ya...> wrote:

> >
>
> >But I got error when compiling another class. It has group.h and
> group.cpp file.
> >
> >
> >#ifndef __GROUP_H
> >#define __GROUP_H
> >
> >
> >#include <string>
> >
> >
> >namespace kaimei{
> >...
> }
> >
> >
> >namespace cppcms {
> >  namespace json {
> >    template<>
> >      struct traits<kaimei::group> {
> >...
> >      }
> >  }
> >}
> >
> >
> >
> > [snip]
> >
> >I am not good at template programming. Why did this happen?
> >
>
> You can't specialize undefined struct - you need to include <cppcms/json.h>
> header. It provides the original traits struct and than you specialize it
> for
> your type of class
>
>
> >
> >陈抒
> >Best regards
> >http://blog.csdn.net/sheismylife
> >
>
> Regards,
> Artyom
>
>
>
> ------------------------------------------------------------------------------
> Live Security Virtual Conference
> Exclusive live event will cover all the ways today's security and
> threat landscape has changed and how IT managers can respond. Discussions
> will include endpoint security, mobile security and the latest in malware
> threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/
> _______________________________________________
> Cppcms-users mailing list
> Cpp...@li...
> https://lists.sourceforge.net/lists/listinfo/cppcms-users
>