//  (C) Copyright John Maddock 2000.
 //  Use, modification and distribution are subject to 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)
 
 //  See http://www.boost.org/libs/static_assert for documentation.
 
 /*
  Revision history:
    02 August 2000
       Initial version.
 */
 
 #ifndef BOOST_STATIC_ASSERT_HPP
 #define BOOST_STATIC_ASSERT_HPP
 
 #include <boost/config.hpp>
 #include <boost/detail/workaround.hpp>
 
 #ifdef __BORLANDC__
 //
 // workaround for buggy integral-constant expression support:
 #define BOOST_BUGGY_INTEGRAL_CONSTANT_EXPRESSIONS
 #endif
 
 #if defined(__GNUC__) && (__GNUC__ == 3) && ((__GNUC_MINOR__ == 3) || (__GNUC_MINOR__ == 4))
 // gcc 3.3 and 3.4 don't produce good error messages with the default version:
 #  define BOOST_SA_GCC_WORKAROUND
 #endif
 
 //
 // If the compiler issues warnings about old C style casts,
 // then enable this:
 //
 #if defined(__GNUC__) && ((__GNUC__ > 3) || ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 4)))
 #  define BOOST_STATIC_ASSERT_BOOL_CAST( x ) ((x) == 0 ? false : true)
 #else
 #  define BOOST_STATIC_ASSERT_BOOL_CAST(x) (bool)(x)
 #endif
 
 #ifdef BOOST_HAS_STATIC_ASSERT
 #  define BOOST_STATIC_ASSERT( B ) static_assert(B, #B)
 #else
 
 namespace boost{
 
 // HP aCC cannot deal with missing names for template value parameters
 template <bool x> struct STATIC_ASSERTION_FAILURE;
 
 template <> struct STATIC_ASSERTION_FAILURE<true> { enum { value = 1 }; };
 
 // HP aCC cannot deal with missing names for template value parameters
 template<int x> struct static_assert_test{};
 
 }
 
 //
 // Implicit instantiation requires that all member declarations be
 // instantiated, but that the definitions are *not* instantiated.
 //
 // It's not particularly clear how this applies to enum's or typedefs;
 // both are described as declarations [7.1.3] and [7.2] in the standard,
 // however some compilers use "delayed evaluation" of one or more of
 // these when implicitly instantiating templates.  We use typedef declarations
 // by default, but try defining BOOST_USE_ENUM_STATIC_ASSERT if the enum
 // version gets better results from your compiler...
 //
 // Implementation:
 // Both of these versions rely on sizeof(incomplete_type) generating an error
 // message containing the name of the incomplete type.  We use
 // "STATIC_ASSERTION_FAILURE" as the type name here to generate
 // an eye catching error message.  The result of the sizeof expression is either
 // used as an enum initialiser, or as a template argument depending which version
 // is in use...
 // Note that the argument to the assert is explicitly cast to bool using old-
 // style casts: too many compilers currently have problems with static_cast
 // when used inside integral constant expressions.
 //
 #if !defined(BOOST_BUGGY_INTEGRAL_CONSTANT_EXPRESSIONS)
 
 #if defined(BOOST_MSVC) && (BOOST_MSVC < 1300)
 // __LINE__ macro broken when -ZI is used see Q199057
 // fortunately MSVC ignores duplicate typedef's.
 #define BOOST_STATIC_ASSERT( B ) \
    typedef ::boost::static_assert_test<\
       sizeof(::boost::STATIC_ASSERTION_FAILURE< (bool)( B ) >)\
       > boost_static_assert_typedef_
 #elif defined(BOOST_MSVC)
 #define BOOST_STATIC_ASSERT( B ) \
    typedef ::boost::static_assert_test<\
       sizeof(::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST ( B ) >)>\
          BOOST_JOIN(boost_static_assert_typedef_, __COUNTER__)
 #elif defined(BOOST_INTEL_CXX_VERSION) || defined(BOOST_SA_GCC_WORKAROUND)
 // agurt 15/sep/02: a special care is needed to force Intel C++ issue an error 
 // instead of warning in case of failure
 # define BOOST_STATIC_ASSERT( B ) \
     typedef char BOOST_JOIN(boost_static_assert_typedef_, __LINE__) \
         [ ::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST( B ) >::value ]
 #elif defined(__sgi)
 // special version for SGI MIPSpro compiler
 #define BOOST_STATIC_ASSERT( B ) \
    BOOST_STATIC_CONSTANT(bool, \
      BOOST_JOIN(boost_static_assert_test_, __LINE__) = ( B )); \
    typedef ::boost::static_assert_test<\
      sizeof(::boost::STATIC_ASSERTION_FAILURE< \
        BOOST_JOIN(boost_static_assert_test_, __LINE__) >)>\
          BOOST_JOIN(boost_static_assert_typedef_, __LINE__)
 #elif BOOST_WORKAROUND(__MWERKS__, <= 0x3003)
 // special version for CodeWarrior <= 8.x
 #define BOOST_STATIC_ASSERT( B ) \
    BOOST_STATIC_CONSTANT(int, \
      BOOST_JOIN(boost_static_assert_test_, __LINE__) = \
        sizeof(::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST( B ) >) )
 #else
 // generic version
 #define BOOST_STATIC_ASSERT( B ) \
    typedef ::boost::static_assert_test<\
       sizeof(::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST( B ) >)>\
          BOOST_JOIN(boost_static_assert_typedef_, __LINE__)
 #endif
 
 #else
 // alternative enum based implementation:
 #define BOOST_STATIC_ASSERT( B ) \
    enum { BOOST_JOIN(boost_static_assert_enum_, __LINE__) \
       = sizeof(::boost::STATIC_ASSERTION_FAILURE< (bool)( B ) >) }
 #endif
 #endif // ndef BOOST_HAS_STATIC_ASSERT
 
 #endif // BOOST_STATIC_ASSERT_HPP