Re: [Boost-users] recursive variant with mpl::vector

Got it... typedef mpl::transform < VariantTypes, boost::unwrap_recursive mpl::_1

::type BaseVariantTypes ;

template <class T> struct variant_type : public mpl::if_ < typename mpl::contains ::type, valid_type<T>, invalid_type<T> >::type { }; Thanks, Surya On Fri, May 21, 2010 at 14:18, Surya Kiran Gullapalli < suryakiran.gullapalli@gmail.com> wrote:

Hello all, I'm trying to create a recursive variant over an MPL vector.http://?shva=1#drafts/128ba01f42cb2169

attached is the code.

I'm trying to add a templated function isType, which will return true if the type stored in variant is the type queried for or false otherwise.

This doesn't work for recursive types.

In the example, I expect the program outputs "Map Type" because the type stored in the variant is a map. but it says the type is not map.

The problem is mpl::contains returns false for map type. (The type stored in mpl vector is boost::recursive_wrapper< map ... >, where as, I'm querying for map...). what is the way forward from here.

Thanks, Surya.