initial commit

oscar64/include/opp/optional.h

@@ -0,0 +1,112 @@
+#ifndef OPP_OPTIONAL_H
+#define OPP_OPTIONAL_H
+
+#include <opp/utility.h>
+
+namespace opp {
+
+template <class T>
+class optional
+{
+protected:
+	char	_data[sizeof(T)];
+	bool	valid;
+public:
+	optional(void) : valid(false) {}
+	optional(const T & data) : valid(true) 
+	{
+		new (_data)T(data);
+	}
+
+	optional(T && data) : valid(true) 
+	{
+		new (_data)T(opp::move(data));
+	}
+
+	optional(const optional<T> & o)
+		: valid(o.valid)
+	{
+		if (valid)
+			new (_data)T(*((T*)o._data));
+	}
+
+	optional(optional<T> && o)
+		: valid(o.valid)
+	{
+		if (valid)
+			new (_data)T(opp::move(*((T*)o._data)));
+	}
+
+	~optional(void)
+	{
+		if (valid)
+			((T*)_data)->~T();
+	}
+
+	optional<T> & operator=(const optional<T> & o)
+	{
+		if (this != &o)
+		{
+			if (valid)
+				((T*)_data)->~T();
+			valid = o.valid;
+			if (valid)
+				new (_data)T(*((T*)o._data));
+		}
+		return *this;
+	}
+
+	optional<T> & operator=(optional<T> && o)
+	{
+		if (this != &o)
+		{
+			if (valid)
+				((T*)_data)->~T();
+			valid = o.valid;
+			if (valid)
+				new (_data)T(opp::move(*((T*)o._data)));
+		}
+		return *this;
+	}
+
+	operator bool(void) const {return valid;}
+	T & operator *(void) const {return *(T*)_data;}
+	const T & operator *(void) const {return *(T*)_data;}
+
+	const T * operator->(void) const {return (T*)_data;}
+
+	T * begin(void)
+	{
+		return (T*)_data;
+	}
+
+	const T * begin(void) const
+	{
+		return (T*)_data;
+	}
+
+	const T * cbegin(void) const
+	{
+		return (T*)_data;
+	}
+
+	T * end(void)
+	{
+		return (T*)_data + (valid ? 1 : 0);
+	}
+
+	const T * end(void) const
+	{
+		return (T*)_data + (valid ? 1 : 0);
+	}
+
+	const T * cend(void) const
+	{
+		return (T*)_data + (valid ? 1 : 0);
+	}
+
+};
+
+}
+
+#endif