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authorheavydemon21 <nielsstunnebrink1@gmail.com>2024-11-21 20:35:09 +0100
committerheavydemon21 <nielsstunnebrink1@gmail.com>2024-11-21 20:35:09 +0100
commitad0dcad1f11d698abf71bf69fb0927c26298d253 (patch)
tree3e8a501a84682ca2b6c085a987666c9b777bc1c7 /src/crepe/util/OptionalRef.h
parentbdc81e355e5bee5d2a3e29346ba08f7bc55196ca (diff)
parent115d6f50152dc018073345800ca90b85846ebaa9 (diff)
Merge branch 'master' into niels/decoupling_pixel_and_pos
Diffstat (limited to 'src/crepe/util/OptionalRef.h')
-rw-r--r--src/crepe/util/OptionalRef.h58
1 files changed, 58 insertions, 0 deletions
diff --git a/src/crepe/util/OptionalRef.h b/src/crepe/util/OptionalRef.h
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+++ b/src/crepe/util/OptionalRef.h
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+#pragma once
+
+namespace crepe {
+
+/**
+ * \brief Optional reference utility
+ *
+ * This class doesn't need to know the full definition of \c T to be used.
+ *
+ * \tparam T Value type
+ */
+template <typename T>
+class OptionalRef {
+public:
+ //! Initialize empty (nonexistant) reference
+ OptionalRef() = default;
+ //! Initialize reference with value
+ OptionalRef(T & ref);
+ /**
+ * \brief Assign new reference
+ *
+ * \param ref Reference to assign
+ *
+ * \return Reference to this (required for operator)
+ */
+ OptionalRef<T> & operator=(T & ref);
+ /**
+ * \brief Retrieve this reference
+ *
+ * \returns Internal reference if it is set
+ *
+ * \throws std::runtime_error if this function is called while the reference it not set
+ */
+ operator T &() const;
+ /**
+ * \brief Check if this reference is not empty
+ *
+ * \returns `true` if reference is set, or `false` if it is not
+ */
+ explicit operator bool() const noexcept;
+
+ /**
+ * \brief Make this reference empty
+ */
+ void clear() noexcept;
+
+private:
+ /**
+ * \brief Reference to the value of type \c T
+ *
+ * \note This raw pointer is *not* managed, and only used as a reference!
+ */
+ T * ref = nullptr;
+};
+
+} // namespace crepe
+
+#include "OptionalRef.hpp"