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Subject: Re: [boost] hash_fwd dependency (Was: New dependency report)
From: Daniel James (dnljms_at_[hidden])
Date: 2014-06-08 06:56:54

On 7 June 2014 17:41, Peter Dimov <lists_at_[hidden]> wrote:
> Antony Polukhin wrote:
>> Would it be good to move a single <boost/functional/hash/hash_fwd.hpp>
>> header into the Boost.Core?
>> This header depends only on Boost.Config. It adds dependency to a whole
>> Boost.Functional library for the following libraries: array, container,
>> filesystem, multiindex, thread, type_index, variant.
> While the general subject of forwarding headers still deserves
> consideration, in this specific case I wonder if moving funcional/hash into
> its own 'hash' module would not alleviate most of the problem.

The point of the forwarding header was to be a lightweight header,
because the main header is quite heavy, so separating out the
forwarding header is probably the right thing to do. I can't guarantee
that I won't add any new dependencies to hash, so if you rely on hash
having less dependencies, then this problem might resurface in the

Looking at your report, many of functional's dependencies seem to be
caused by problems elsewhere, e.g. boost/functional/factory.hpp
includes boost/pointee.hpp from iterator, which pulls in a lot of
modules. I think the problem there is with boost/pointee.hpp.

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