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[/
Copyright 1999-2003 Beman Dawes
Copyright 2014 Peter Dimov
Distributed under the Boost Software License, Version 1.0.
See accompanying file LICENSE_1_0.txt
or copy at http://boost.org/LICENSE_1_0.txt
]
[section:noncopyable noncopyable]
[simplesect Authors]
* Dave Abrahams
[endsimplesect]
[section Header <boost/core/noncopyable.hpp>]
The header `<boost/core/noncopyable.hpp>` defines the class
`boost::noncopyable`. It is intended to be used as a private
base class. `boost::noncopyable` has private (under C++03) or
deleted (under C++11) copy constructor and a copy assignment
operator and can't be copied or assigned; a class that derives
from it inherits these properties.
`boost::noncopyable` was originally contributed by Dave
Abrahams.
[section Synopsis]
``
namespace boost
{
class noncopyable;
}
``
[endsect]
[section Example]
``
#include <boost/core/noncopyable.hpp>
class X: private boost::noncopyable
{
};
``
[endsect]
[section Rationale]
Class noncopyable has protected constructor and destructor members to emphasize
that it is to be used only as a base class. Dave Abrahams notes concern about
the effect on compiler optimization of adding (even trivial inline) destructor
declarations. He says:
["Probably this concern is misplaced, because `noncopyable` will be used mostly
for classes which own resources and thus have non-trivial destruction semantics.]
With C++2011, using an optimized and trivial constructor and similar destructor
can be enforced by declaring both and marking them `default`. This is done in
the current implementation.
[endsect]
[endsect]
[endsect]
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