math/tools/complex.hpp

0001 //  Copyright John Maddock 2018.
0002 //  Use, modification and distribution are subject to the
0003 //  Boost Software License, Version 1.0. (See accompanying file
0004 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0005
0006 //
0007 // Tools for operator on complex as well as scalar types.
0008 //
0009
0010 #ifndef BOOST_MATH_TOOLS_COMPLEX_HPP
0011 #define BOOST_MATH_TOOLS_COMPLEX_HPP
0012
0013 #include <utility>
0014 #include <boost/math/tools/is_detected.hpp>
0015
0016 namespace boost {
0017    namespace math {
0018       namespace tools {
0019
0020          namespace detail {
0021          template <typename T, typename = void>
0022          struct is_complex_type_impl
0023          {
0024             static constexpr bool value = false;
0025          };
0026
0027          template <typename T>
0028          struct is_complex_type_impl<T, void_t<decltype(std::declval<T>().real()),
0029                                                decltype(std::declval<T>().imag())>>
0030          {
0031             static constexpr bool value = true;
0032          };
0033          } // Namespace detail
0034
0035          template <typename T>
0036          struct is_complex_type : public detail::is_complex_type_impl<T> {};
0037
0038          //
0039          // Use this trait to typecast integer literals to something
0040          // that will interoperate with T:
0041          //
0042          template <class T, bool = is_complex_type<T>::value>
0043          struct integer_scalar_type
0044          {
0045             typedef int type;
0046          };
0047          template <class T>
0048          struct integer_scalar_type<T, true>
0049          {
0050             typedef typename T::value_type type;
0051          };
0052          template <class T, bool = is_complex_type<T>::value>
0053          struct unsigned_scalar_type
0054          {
0055             typedef unsigned type;
0056          };
0057          template <class T>
0058          struct unsigned_scalar_type<T, true>
0059          {
0060             typedef typename T::value_type type;
0061          };
0062          template <class T, bool = is_complex_type<T>::value>
0063          struct scalar_type
0064          {
0065             typedef T type;
0066          };
0067          template <class T>
0068          struct scalar_type<T, true>
0069          {
0070             typedef typename T::value_type type;
0071          };
0072
0073
0074 } } }
0075
0076 #endif // BOOST_MATH_TOOLS_COMPLEX_HPP