boost_1_45_0/libs/type_traits/doc/mpl.qbk

[/ 
  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:mpl MPL Interoperability]

All the value based traits in this library conform to MPL's requirements
for an [@../../../../libs/mpl/doc/refmanual/integral-constant.html Integral Constant type]: that includes a number of rather intrusive
workarounds for broken compilers.  

Purely as an implementation detail, this
means that `__true_type` inherits from [@../../../../libs/mpl/doc/refmanual/bool.html `boost::mpl::true_`], `__false_type` inherits
from [@../../../../libs/mpl/doc/refmanual/bool.html `boost::mpl::false_`], and `__integral_constant<T, v>` inherits from
[@../../../../libs/mpl/doc/refmanual/integral-c.html `boost::mpl::integral_c<T,v>`] (provided `T` is not `bool`)

[endsect]