Re: [Boost-users] binary mpl::transform fails to compile with fusion::vector

Subject: Re: [Boost-users] binary mpl::transform fails to compile with fusion::vector
From: Joel de Guzman (joel_at_[hidden])
Date: 2009-06-22 00:37:32

Aleksey Gurtovoy wrote:

> No, the error is caused by the following code in MPL's pair_view
> (which is the underlying implementation mechanism for the binary
> transform):
> 
>     typedef typename min<
>           typename iterator_category<iter1_>::type
>         , typename iterator_category<iter2_>::type
>         >::type category_;
> 
> That is, as per iterator_category's requirements [1], pair_view
> assumes that the iterator_category's result would be model of
> MPL's Integral Constant, which does not seem to be the case with
> Fusion categories.
> 
> [1] 
> http://www.boost.org/doc/libs/1_39_0/libs/mpl/doc/refmanual/iterator-category.html 

I see. It's a fusion bug then. I'll see what I can do. In the meantime,
may I request the OP to add a trac ticket entry for this?

Thank you, Aleksey!

Regards,
-- 
Joel de Guzman
http://www.boostpro.com
http://spirit.sf.net