[/ 
  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:is_unsigned is_unsigned]

   template <class T>
   struct is_unsigned : public __tof {};
  
__inherit If T is an unsigned integer type or an enumerated type with an
underlying unsigned integer type, then inherits from __true_type, 
otherwise inherits from __false_type.

__std_ref 3.9.1, 7.2.

[all_compilers]

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

__examples

[:`is_unsigned<unsigned int>` inherits from `__true_type`.]

[:`is_unsigned<unsigned int const volatile>::type` is the type `__true_type`.]

[:`is_unsigned<int>::value` is an integral constant 
expression that evaluates to /false/.]

[:`is_unsigned<myclass>::value` is an integral constant 
expression that evaluates to /false/.]

[:`is_unsigned<char>::value` is an integral constant 
expression whose value depends upon the signedness of type `char`.]

[:`is_unsigned<unsigned long long>::value` is an integral constant 
expression that evaluates to /true/.]

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

[endsect]

