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<functional>
headerSection: 22.10 [function.objects] Status: NAD Submitter: BSI Opened: 2010-08-25 Last modified: 2016-01-28
Priority: Not Prioritized
View all other issues in [function.objects].
View all issues with NAD status.
Discussion:
Addresses GB-96
The function templates hash
, less
and equal_to
are important customization points for user-defined types to
be supported by several standard containers. These are
accessed through the <functional>
header which has
grown significantly larger in C++0x, exposing many more
facilities than a user is likely to need through there own
header, simply to declare the necessary specialization.
There should be a smaller header available for users to
make the necessary customization.
[ Resolution proposed by ballot comment ]
Provide a tiny forwarding header for important
functor types in the <functional>
header that a
user may want to specialize. This should contain
the template declaration for equal_to
, hash
and
less
.
[ Rapperswill summary ]
Alisdair: Would recommend NAD unless someone takes the issue.
Daniel: Volunteers to write a paper for this.
[ 2010-11-07 Daniel provides a paper available on the Batavia document list ]
[ 2010 Batavia: ]
Closed as NAD - the consensus was that forwarding headers such as
<iosfwd>
do not bring the expected benefits, and are
not widely used (to the surprise of some active users in the room!).
Without real experience reporting a benefit, there is no further interest
in pursuing this issue as an extension - hence NAD rather than NAD Future.
Rationale:
No consensus to make a change
Proposed resolution:
See paper "Forwarding <functional>
functor templates"
on the Batavia LWG document list