Re: [Boost-users] boost::variant compile error

Subject: Re: [Boost-users] boost::variant compile error
From: Jeffrey Lee Hellrung, Jr. (jeffrey.hellrung_at_[hidden])
Date: 2012-11-09 09:12:49

On Thu, Nov 8, 2012 at 11:44 PM, <Georg.Kellerer_at_[hidden]> wrote:

> Hi,
>
> i'd like to build a heterogenous container based on the boost::variant
> datastructure. My code looks like this:
> // forward-Deklarationen:
> class fExport FB_Ordered;
> class fExport FB_Dictionary;
>

What's fExport?

> // Typedefs
> typedef boost::variant<int, std::string> keydicttype;
> typedef boost::variant<
>         int, std::string, date, ptime,
>         boost::recursive_wrapper<FB_Dictionary>,
>         boost::recursive_wrapper<FB_Ordered>> valuedicttype;
> typedef boost::container::map<keydicttype, valuedicttype> basedict;
>
> C:\dev\boost_1_52_0\boost/checked_delete.hpp(32) : error C2027: use of
> undefined Type "FB_Ordered"
>
> what i want to do is to create a container fb_dictionary which can hold
> datatypes that are listed in the valuedicttype and which can accept
> keyvalues of int and string (see above). fb_ordered is another container
> defined in a diferent header file so i need the forward declarations. Could
> anybody please give me a hint in the right direction?  I am using vs2008.
>

A full, expected-to-compile example is always helpful. But the errors I'm
getting with the above typedefs seem more related to the lack of this
fExport keyword you're using. If I remove the fExport stuff then all the
typedefs compile fine, and I don't get the undefined type error until I try
to instantiate basedict (obviously; FB_Ordered and FB_Dictionary need to be
defined by then).

- Jeff