Merge pull request #53 from MtFmT-Lib/good_cpp_header

CXX: result, 更好的约束写法

inc/mm_helper.hpp

@@ -0,0 +1,171 @@
+// SPDX-License-Identifier: LGPL-3.0
+/**
+ * @file    mm_helper.hpp
+ * @author  向阳 (hinata.hoshino@foxmail.com)
+ * @brief   helper
+ * @version 1.0
+ * @date    2023-06-15
+ *
+ * @copyright Copyright (c) 向阳, all rights reserved.
+ *
+ */
+#if !defined(_INCLUDE_MM_HELPER_HPP_)
+#define _INCLUDE_MM_HELPER_HPP_ 1
+#include <cstddef>
+#include <exception>
+#include <tuple>
+#include <type_traits>
+#include <utility>
+namespace mtfmt
+{
+namespace details
+{
+/**
+ * @brief 单位类型
+ *
+ */
+struct unit_t
+{
+};
+
+/**
+ * @brief 用于存放函数类型信息的东东
+ */
+template <typename Ret, typename... Args> struct function_traits_base
+{
+    //! 返回值类型
+    using return_type_t = Ret;
+    //! 参数数目
+    static constexpr size_t NArgs = sizeof...(Args);
+    //! 参数(元组)
+    using arg_tuple_t = std::tuple<Args...>;
+};
+
+template <typename F> struct function_trait_impl;
+
+template <typename F>
+struct function_trait_impl<std::reference_wrapper<F>>
+    : public function_trait_impl<F>
+{
+};
+
+// for: function pointer
+template <typename Ret, typename... Args>
+struct function_trait_impl<Ret (*)(Args...)>
+    : public function_traits_base<Ret, Args...>
+{
+};
+
+// for: lambda函数
+template <typename Ret, typename Cl, typename... Args>
+struct function_trait_impl<Ret (Cl::*)(Args...)>
+    : public function_traits_base<Ret, Args...>
+{
+};
+
+// for: lambda函数(不可变capture)
+template <typename Ret, typename Cl, typename... Args>
+struct function_trait_impl<Ret (Cl::*)(Args...) const>
+    : public function_traits_base<Ret, Args...>
+{
+};
+
+// 除去如上三种情况的case
+template <typename F>
+struct function_trait_impl
+    : public function_trait_impl<decltype(&F::operator())>
+{
+};
+
+/**
+ * @brief 取得函数的各种细节
+ *
+ */
+template <typename F>
+struct function_trait
+    : public function_trait_impl<typename std::decay<F>::type>
+{
+};
+
+/**
+ * @brief 取得函数的返回值类型
+ *
+ */
+template <typename F>
+using function_return_type_t =
+    typename function_trait<F>::return_type_t;
+
+/**
+ * @brief 取得函数的参数类型
+ *
+ */
+template <typename F>
+using function_arg_tuple_t = typename function_trait<F>::arg_tuple_t;
+
+/**
+ * @brief 取得函数的参数的个数
+ *
+ */
+template <typename F> struct function_arg_count
+{
+    static constexpr std::size_t N = function_trait<F>::NArgs;
+};
+
+/**
+ * @brief 判断Ti是否为模板Tt的实例化
+ *
+ */
+template <template <typename...> typename Tt, typename Ti>
+struct is_instance_of
+{
+    static constexpr bool value = false;
+};
+
+// 判断Ti是否为模板Tt的实例化
+template <template <typename...> typename Tt, typename... Ti>
+struct is_instance_of<Tt, Tt<Ti...>>
+{
+    static constexpr bool value = true;
+};
+
+/**
+ * @brief 表示检查函数参数有多少个
+ *
+ */
+template <typename F, std::size_t N> struct function_has_n_args
+{
+    static constexpr bool value = function_arg_count<F>::N == N;
+};
+
+/**
+ * @brief 表示第n个参数应该拥有类型T
+ *
+ */
+template <typename F, std::size_t N, typename T>
+struct function_args_hold_type
+{
+    static constexpr bool value = std::is_same<
+        // 取得第n个参数
+        typename std::tuple_element<N, function_arg_tuple_t<F>>::type,
+        // 并检查其拥有的类型
+        T>::value;
+};
+
+/**
+ * @brief 检查函数F的类型为 ( T1, T2 ...) -> R
+ *
+ */
+template <typename F, typename R, typename... T> struct holds_prototype
+{
+    using _Ret = details::function_return_type_t<F>;
+    using _Args = details::function_arg_tuple_t<F>;
+    using Targs = std::tuple<typename std::decay<T>::type...>;
+
+    static constexpr bool value =
+        function_has_n_args<F, sizeof...(T)>::value &&
+        std::is_same<_Ret, R>::value &&
+        std::is_same<_Args, Targs>::value;
+};
+} // namespace details
+} // namespace mtfmt
+#endif // _INCLUDE_MM_HELPER_HPP_

inc/mm_parser.hpp

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: LGPL-3.0
+/**
+ * @file    mm_parser.hpp
+ * @author  向阳 (hinata.hoshino@foxmail.com)
+ * @brief   分析器 (CPP frontend)
+ * @version 1.0
+ * @date    2023-06-15
+ *
+ * @copyright Copyright (c) 向阳, all rights reserved.
+ *
+ */
+#if !defined(_INCLUDE_MM_PARSER_HPP_)
+#define _INCLUDE_MM_PARSER_HPP_ 1
+
+#endif // _INCLUDE_MM_PARSER_HPP_