Abstract prep to be more independent

1 files changed, 154 insertions, 0 deletions

diff --git a/modules/core/c++/abstract/common.hpp b/modules/core/c++/abstract/common.hpp
new file mode 100644
index 0000000..408946c
--- /dev/null
+++ b/modules/core/c++/abstract/common.hpp
@@ -0,0 +1,154 @@
+#pragma once
+
+#include <cstdint>
+#include <memory>
+#include <optional>
+#include <utility>
+
+namespace saw {
+
+#define KEL_CONCAT_(x, y) x##y
+#define KEL_CONCAT(x, y) KEL_CONCAT_(x, y)
+#define KEL_UNIQUE_NAME(prefix) KEL_CONCAT(prefix, __LINE__)
+
+#define KEL_FORBID_COPY(classname)                                             \
+	classname(const classname &) = delete;                                     \
+	classname &operator=(const classname &) = delete
+
+#define KEL_FORBID_MOVE(classname)                                             \
+	classname(classname &&) = delete;                                          \
+	classname &operator=(classname &&) = delete
+
+#define KEL_DEFAULT_COPY(classname)                                            \
+	classname(const classname &) = default;                                    \
+	classname &operator=(const classname &) = default
+
+#define KEL_DEFAULT_MOVE(classname)                                            \
+	classname(classname &&) = default;                                         \
+	classname &operator=(classname &&) = default
+
+// In case of C++20
+#define KEL_ASSERT(expression)                                                 \
+	assert(expression);                                                        \
+	if (!(expression)) [[unlikely]]
+
+template <typename T> using maybe = std::optional<T>;
+
+template <typename T> using own = std::unique_ptr<T>;
+
+template <typename T> using our = std::shared_ptr<T>;
+
+template <typename T> using lent = std::weak_ptr<T>;
+
+template<typename T>
+class ptr {
+private:
+	T* ptr_;
+
+public:
+	ptr():
+		ptr_{nullptr}
+	{}
+
+	ptr(T& ptr__):
+		ptr_{&ptr__}
+	{}
+
+	KEL_DEFAULT_COPY(ptr);
+	KEL_DEFAULT_MOVE(ptr);
+
+	T& operator()(){
+		return *ptr_;
+	}
+
+	const T& operator()() const {
+		return *ptr_;
+	}
+
+	bool is_valid() const {
+		return ptr_ != nullptr;
+	}
+};
+
+/**
+ * Reference class for easier distinction
+ * of references and its referenced types.
+ */
+template <typename T>
+class ref {
+private:
+	/**
+	 * Referenced type
+	 */
+	T* ref_;
+
+	/**
+	 * We don't want to move since the would invalidate the type.
+	 */
+	KEL_FORBID_MOVE(ref);
+public:
+	/**
+	 * Main constructor.
+	 */
+	constexpr ref(T& ref__):
+		ref_{&ref__}
+	{}
+
+	KEL_DEFAULT_COPY(ref);
+
+	/**
+	 * Operator retrieving the itself.
+	 */
+	constexpr T& operator()(){
+		return *ref_;
+	}
+
+	/**
+	 * Operator retrieving the itself.
+	 */
+	constexpr const T& operator()() const {
+		return *ref_;
+	}
+};
+
+template <typename T, class... Args> own<T> heap(Args &&...args) {
+	return own<T>(new T(std::forward<Args>(args)...));
+}
+
+template <typename T, class... Args> our<T> share(Args &&...args) {
+	return std::make_shared<T>(std::forward<Args>(args)...);
+}
+
+template <typename T> T instance() noexcept;
+
+template <typename Func, typename T> struct return_type_helper {
+	typedef decltype(instance<Func>()(instance<T>())) Type;
+};
+template <typename Func> struct return_type_helper<Func, void> {
+	typedef decltype(instance<Func>()()) Type;
+};
+
+template <typename Func, typename T>
+using return_type = typename return_type_helper<Func, T>::Type;
+
+/**
+ * Struct describing a void type
+ */
+struct void_t {};
+
+/**
+ * Helper function since changing returns between void_t{} and make_error<...>() is a bit annoying.
+ */
+void_t make_void();
+
+template <typename T> struct void_fix { typedef T Type; };
+template <> struct void_fix<void> { typedef void_t Type; };
+template <typename T> using fix_void = typename void_fix<T>::Type;
+
+template <typename T> struct void_unfix { typedef T Type; };
+template <> struct void_unfix<void_t> { typedef void Type; };
+template <typename T> using unfix_void = typename void_unfix<T>::Type;
+
+template <typename... T> constexpr bool always_false = false;
+
+} // namespace saw