[boost] [fusion] mpl::clear doesn't work on fusion views

Subject: [boost] [fusion] mpl::clear doesn't work on fusion views
From: Eric Niebler (eric_at_[hidden])
Date: 2011-07-29 15:52:49

Today I ran into a limitation in Fusion/MPL interoperability. I couldn't
use an mpl algorithm on a Fusion sequence because mpl::clear wasn't
defined on it. The sequence was a joint_view. I see that
fusion::detail::clear is only defined for Fusion cons, map, set, vector
and deque. Can we get it defined for all Fusion sequences? I think for
everything else, an empty Fusion vector would do. That is all
fusion::clear does, btw.

(Aside: it seems strange to me that mpl::clear of a fusion::set gives an
empty set, but that fusion::clear of an empty set gives an empty vector.
This should probably be made consistent.)

-- 
Eric Niebler
BoostPro Computing
http://www.boostpro.com