has_nothrow_copy.qbk

来自「Boost provides free peer-reviewed portab」· QBK 代码 · 共 35 行

[/ 
  Copyright 2007 John Maddock.
  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:has_nothrow_copy has_nothrow_copy]

   template <class T>
   struct has_nothrow_copy : public __tof {};
  
   template <class T>
   struct has_nothrow_copy_constructor : public __tof {};
  
__inherit If T is a (possibly cv-qualified) type with a non-throwing copy-constructor
then inherits from __true_type, otherwise inherits from __false_type.  Type `T`
must be a complete type.

These two traits are synonyms for each other.

__compat If the compiler does not support partial-specialization of class 
templates, then this template can not be used with function types.

Without some (as yet unspecified) help from the compiler, 
`has_nothrow_copy` will never report that a class or struct has a 
non-throwing copy-constructor; this is always safe, if possibly sub-optimal.
Currently (May 2005) only Visual C++ 8 has the necessary compiler __intrinsics to ensure that this
trait "just works".

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

[endsect]