Imported Upstream version 1.49.0upstream/1.49.0

1 files changed, 99 insertions, 0 deletions

diff --git a/boost/ratio/detail/mpl/gcd.hpp b/boost/ratio/detail/mpl/gcd.hpp
new file mode 100644
index 0000000000..59a09714cd
--- /dev/null
+++ b/boost/ratio/detail/mpl/gcd.hpp
@@ -0,0 +1,99 @@
+////////////////////////////////////////////////////////////////////
+//
+// Copyright Vicente J. Botet Escriba 2010
+//
+// 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)
+//
+// See http://www.boost.org/libs/mpl for documentation.
+//
+////////////////////////////////////////////////////////////////////
+#ifndef BOOST_MPL_GCD_HPP_INCLUDED
+#define BOOST_MPL_GCD_HPP_INCLUDED
+
+#include <boost/mpl/integral_c.hpp>
+#include <boost/ratio/detail/mpl/abs.hpp>
+#include <boost/mpl/aux_/largest_int.hpp>
+#include <boost/mpl/aux_/na_spec.hpp>
+#include <boost/mpl/aux_/lambda_support.hpp>
+#include <boost/mpl/aux_/config/eti.hpp>
+#include <boost/mpl/aux_/config/integral.hpp>
+#include <boost/mpl/aux_/config/static_constant.hpp>
+
+#if    !defined(BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2) \
+    && !defined(BOOST_MPL_PREPROCESSING_MODE) \
+    && ( defined(BOOST_MSVC) \
+        || BOOST_WORKAROUND(__EDG_VERSION__, <= 238) \
+        )
+
+#   define BOOST_MPL_CFG_NO_NESTED_VALUE_ARITHMETIC_2
+
+#endif
+
+namespace boost { namespace mpl {
+
+template< typename Tag1, typename Tag2 > struct gcd_impl;
+
+template< typename T > struct gcd_tag
+{
+    typedef typename T::tag type;
+};
+
+template<
+      typename BOOST_MPL_AUX_NA_PARAM(N1)
+    , typename BOOST_MPL_AUX_NA_PARAM(N2)
+    >
+struct gcd
+    : gcd_impl<
+          typename gcd_tag<N1>::type
+        , typename gcd_tag<N2>::type
+        >::template apply<N1, N2>::type
+{
+    BOOST_MPL_AUX_LAMBDA_SUPPORT(2, gcd, (N1, N2))
+};
+
+BOOST_MPL_AUX_NA_SPEC(2, gcd)
+
+template<
+      typename T
+    , T n1
+    , T n2
+    >
+struct gcd_c
+    : gcd<integral_c<T,n1>,integral_c<T,n2> >
+{
+};
+
+namespace aux {
+    template< typename T1, T1 n1, bool n1_is_0, typename T2, T2 n2, bool n2_is_0 > 
+    struct gcd_aux
+ 
+        : gcd_aux<T2, n2, n2==0, 
+                    typename aux::largest_int<T1, T2>::type,
+                    //~ T1, 
+                    (n1 % n2), (n1 % n2)==0>
+    {};
+    
+    template <typename T1, T1 n1, typename T2, T2 n2>
+    struct gcd_aux<T1, n1, false, T2, n2, true> : integral_c<T1, n1> 
+    {};
+
+    template <typename T1, T1 n1, typename T2, T2 n2, bool C>
+    struct gcd_aux<T1, n1, true, T2, n2, C> : integral_c<T2, n2> 
+    {};
+}
+
+template<>
+struct gcd_impl<integral_c_tag, integral_c_tag>
+{
+    template< typename N1, typename N2 > struct apply
+        : abs<aux::gcd_aux< typename N1::value_type, N1::value, N1::value==0, 
+                        typename N2::value_type, N2::value, N2::value==0  > >
+    {
+    };
+};
+
+}}
+
+#endif // BOOST_MPL_GCD_HPP_INCLUDED