bump version to 12.2.2-pve1

[ceph.git] / ceph / src / boost / libs / type_traits / doc / is_final.qbk

[/
  Copyright (c) 2014 Agustin Berge
  Distributed under the Boost Software License, Version 1.0.
  (See accompanying file LICENSE_1_0.txt or copy at
  http://www.boost.org/LICENSE_1_0.txt).
]

[section:is_final is_final]
   template <class T>
   struct is_final : public __tof {};

__inherit If T is a (possibly cv-qualified) class type declared with the final
specifier type then inherits from __true_type, otherwise inherits from __false_type.
Currently requires some kind of compiler support.

__std_ref 9p3.

__compat Without (some as yet unspecified) help from the compiler, we cannot detect
class types declared with the final specifier using only standard C++,
as a result this type will never inherit from __true_type, unless the user explicitly
specializes the template for their user-defined final class types, or unless the compiler
supplies some unspecified intrinsic that implements this functionality.
Currently (June 2015) compilers more recent than GCC-4.7, Oracle-12.4, and Clang
have the necessary compiler __intrinsics to ensure that this
trait "just works".  You may also test to see if the necessary __intrinsics are available
by checking to see if the macro `BOOST_IS_FINAL` is defined.

__header ` #include <boost/type_traits/is_final.hpp>` or ` #include <boost/type_traits.hpp>`

__examples

Given `struct my_final final {};` then:

[:`is_final<my_final>` inherits from `__true_type`.]

[:`is_final<const my_final>::type` is the type `__true_type`.]

[:`is_final<my_final>::value` is an integral constant
expression that evaluates to /true/.]

[:`is_final<my_final*>::value` is an integral constant
expression that evaluates to /false/.]

[:`is_final<T>::value_type` is the type `bool`.]

[endsect]