1 files changed, 67 insertions, 0 deletions
diff --git a/src/crepe/util/OptionalRef.hpp b/src/crepe/util/OptionalRef.hpp
new file mode 100644
index 0000000..e603a25
--- /dev/null
+++ b/src/crepe/util/OptionalRef.hpp
@@ -0,0 +1,67 @@
+#pragma once
+
+#include <stdexcept>
+
+#include "OptionalRef.h"
+
+namespace crepe {
+
+template <typename T>
+OptionalRef<T>::OptionalRef(T & ref) {
+	this->set(ref);
+}
+
+template <typename T>
+OptionalRef<T>::OptionalRef(const OptionalRef<T> & other) {
+	this->ref = other.ref;
+}
+
+template <typename T>
+OptionalRef<T>::OptionalRef(OptionalRef<T> && other) {
+	this->ref = other.ref;
+	other.clear();
+}
+
+template <typename T>
+OptionalRef<T> & OptionalRef<T>::operator=(const OptionalRef<T> & other) {
+	this->ref = other.ref;
+	return *this;
+}
+
+template <typename T>
+OptionalRef<T> & OptionalRef<T>::operator=(OptionalRef<T> && other) {
+	this->ref = other.ref;
+	other.clear();
+	return *this;
+}
+
+template <typename T>
+T & OptionalRef<T>::get() const {
+	if (this->ref == nullptr)
+		throw std::runtime_error("OptionalRef: attempt to dereference nullptr");
+	return *this->ref;
+}
+
+template <typename T>
+void OptionalRef<T>::set(T & ref) noexcept {
+	this->ref = &ref;
+}
+
+template <typename T>
+void OptionalRef<T>::clear() noexcept {
+	this->ref = nullptr;
+}
+
+template <typename T>
+OptionalRef<T> & OptionalRef<T>::operator=(T & ref) {
+	this->set(ref);
+	return *this;
+}
+
+template <typename T>
+OptionalRef<T>::operator bool() const noexcept {
+	return this->ref == nullptr;
+}
+
+}
+