Added thirdparty: boost library

thirdparty/include/boost/math/ccmath/isunordered.hpp

@@ -0,0 +1,35 @@
+//  (C) Copyright Matt Borland 2022.
+//  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)
+
+#ifndef BOOST_MATH_CCMATH_ISUNORDERED_HPP
+#define BOOST_MATH_CCMATH_ISUNORDERED_HPP
+
+#include <boost/math/ccmath/detail/config.hpp>
+
+#ifdef BOOST_MATH_NO_CCMATH
+#error "The header <boost/math/isunordered.hpp> can only be used in C++17 and later."
+#endif
+
+#include <boost/math/ccmath/isnan.hpp>
+
+namespace boost::math::ccmath {
+
+template <typename T>
+inline constexpr bool isunordered(const T x, const T y) noexcept
+{
+    if(BOOST_MATH_IS_CONSTANT_EVALUATED(x))
+    {
+        return boost::math::ccmath::isnan(x) || boost::math::ccmath::isnan(y);
+    }
+    else
+    {
+        using std::isunordered;
+        return isunordered(x, y);
+    }
+}
+
+} // Namespaces
+
+#endif // BOOST_MATH_CCMATH_ISUNORDERED_HPP