test, trial, experiments
| 修订版 | 72ab932b7505d9087087d8b9fbed62414705bbfb (tree) |
|---|---|
| 时间 | 2017-03-22 12:52:59 |
| 作者 | Yamashta Daisuke <yamasdais@gmai...> |
| Commiter | Yamashta Daisuke |
added apply<T...>
improved is_cons<T> check
cxx/fmp.cc (diff)| @@ -69,6 +69,15 @@ struct any<cons<A, D>> { | ||
| 69 | 69 | using value_type = cons<A, D>; |
| 70 | 70 | }; |
| 71 | 71 | |
| 72 | +template <typename T> | |
| 73 | +std::false_type check_cons(...); | |
| 74 | + | |
| 75 | +template <typename T> | |
| 76 | +auto check_cons(T*) -> decltype( | |
| 77 | + std::is_same<typename T::car_type, typename T::cdr_type>::value, | |
| 78 | + std::true_type() | |
| 79 | +); | |
| 80 | + | |
| 72 | 81 | } // detail |
| 73 | 82 | |
| 74 | 83 | using nil = detail::nil_type; |
| @@ -99,11 +108,16 @@ struct is_nil : public std::false_type { }; | ||
| 99 | 108 | template <> |
| 100 | 109 | struct is_nil<nil> : public std::true_type { }; |
| 101 | 110 | |
| 111 | +#if 0 | |
| 102 | 112 | template <typename T> |
| 103 | 113 | struct is_cons : public std::false_type { }; |
| 104 | 114 | |
| 105 | 115 | template <typename T0, typename T1> |
| 106 | 116 | struct is_cons<cons<T0, T1>> : std::true_type { }; |
| 117 | +#endif | |
| 118 | +template <typename T> | |
| 119 | +struct is_cons : public decltype(detail::check_cons<T>(nullptr)) { | |
| 120 | +}; | |
| 107 | 121 | |
| 108 | 122 | template <typename T> |
| 109 | 123 | struct is_atom : public std::true_type { }; |
| @@ -169,6 +183,12 @@ struct list { | ||
| 169 | 183 | using apply = typename detail::list_elem<T...>::apply; |
| 170 | 184 | }; |
| 171 | 185 | |
| 186 | +template <template <class...> typename F, | |
| 187 | + typename... Rest> | |
| 188 | +struct apply { | |
| 189 | + using type = typename F<Rest...>::apply; | |
| 190 | +}; | |
| 191 | + | |
| 172 | 192 | template <typename Cond, typename IfTrue, typename IfFalse = nil> |
| 173 | 193 | struct if_t { |
| 174 | 194 | using apply = typename std::conditional< |
| @@ -180,8 +200,10 @@ struct if_t { | ||
| 180 | 200 | |
| 181 | 201 | void test_list() { |
| 182 | 202 | using namespace fmp; |
| 183 | - using l_0 = list<>::apply; // (list) => nil | |
| 184 | - using l_int = list<int>::apply; // (list 'int) => (INT) | |
| 203 | + //using l_0 = list<>::apply; // (list) => nil | |
| 204 | + using l_0 = apply<list>::type; | |
| 205 | + //using l_int = list<int>::apply; // (list 'int) => (INT) | |
| 206 | + using l_int = apply<list, int>::type; | |
| 185 | 207 | using l_2 = list<int, char>::apply; |
| 186 | 208 | using l_3 = list<int, char, float>::apply; |
| 187 | 209 | using l_4 = list<int, char, float, double>::apply; |
| @@ -241,6 +263,7 @@ void test0() { | ||
| 241 | 263 | |
| 242 | 264 | static_assert(eq<int1::value_type, int>::value, "int1 == int"); |
| 243 | 265 | static_assert(int1::value == 1, "val<int, 1> == 1"); |
| 266 | + static_assert(!is_cons<nil>::value, "is_cons<nil> != true"); | |
| 244 | 267 | static_assert(!fmp::is_cons<int>::value, "is_cons<int> != true"); |
| 245 | 268 | static_assert(fmp::is_cons<cint>::value, "is_consp<cint> == true"); |
| 246 | 269 | static_assert(fmp::is_nil<fmp::cons<fmp::nil>::car::value_type>::value, |
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