Re: [Boost-users] [mpl] Where is at with default

Subject: Re: [Boost-users] [mpl] Where is at with default
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2009-10-16 10:49:31

AMDG

Agustín K-ballo Bergé wrote:
> I can't seem to find the `at` metafunction with a default value for
> associative sequences. What should I include to use such metafunction
> with a mpl::map ? Including <boost/mpl/at.hpp> is not enough, I get a
> 'too many templates arguments' when trying to do:
>
> typename boost::mpl::at< State, R, L >::type
>
> which I ended up doing like this:
>
> typename boost::mpl::eval_if<
>     typename boost::mpl::has_key< State, R >::type
>   , boost::mpl::at< State, R >
>   , boost::mpl::identity< L >
>   
>> ::type
>>     

It doesn't exist.  The documentation and the code are not in synch.

In Christ,
Steven Watanabe