Remove optional semantics from identifier

include/tl/epilogue.h

@@ -1,24 +0,0 @@
-#pragma once
-
-#include "tl/functional.h"
-
-namespace tl
-{
-class epilogue
-{
-	public:
-
-	epilogue(function<void()> i_function) noexcept
-		: m_function(std::move(i_function))
-	{
-	}
-
-	~epilogue() noexcept
-	{
-		m_function();
-	}
-private:
-	function<void()> m_function;
-};
-
-}

include/tl/identifier.h

@@ -7,46 +7,43 @@
 namespace tl
 {
 
-template<typename T, T invalid_value, typename Tag>
+template<typename T, typename Tag>
 struct identifier
 {
 	using underlying_type = T;
 
-	constexpr identifier() noexcept = default;
+	identifier() = delete;
 	explicit constexpr identifier(T value) noexcept : m_value(std::move(value)) {}
 
 	constexpr T value() const noexcept { return m_value; }
-	constexpr bool is_valid() const noexcept { return m_value != invalid_value; }
-	//inline static identifier<T, invalid_value, Tag> invalid() noexcept { return identifier<T, invalid_value, Tag>(); }
-
-	auto operator<=>(const identifier<T, invalid_value, Tag>& other) const noexcept { return m_value <=> other.value(); }
+	auto operator<=>(const identifier<T, Tag>& other) const noexcept { return m_value <=> other.value(); }
 	auto operator<=>(const T& other) const noexcept { return m_value <=> other; }
-	bool operator==(const identifier<T, invalid_value, Tag>& other) const noexcept { return m_value == other.value(); }
+	bool operator==(const identifier<T, Tag>& other) const noexcept { return m_value == other.value(); }
 	bool operator==(const T& other) const noexcept { return m_value == other; }
 
 private:
-	T m_value = invalid_value;
+	T m_value;
 };
 }
 
-#define TL_DECLARE_INTEGRAL_ID(NAME, TYPE, INVALID_VALUE) \
+#define TL_DECLARE_INTEGRAL_ID(NAME, TYPE) \
 struct NAME##_tag {};\
-using NAME = tl::identifier<TYPE, INVALID_VALUE, NAME##_tag>;
+using NAME = tl::identifier<TYPE, NAME##_tag>;
 
-template <typename T, T invalid_value, typename Tag>
-struct std::formatter<tl::identifier<T, invalid_value, Tag>>
+template <typename T, typename Tag>
+struct std::formatter<tl::identifier<T, Tag>>
 {
 	constexpr auto parse(format_parse_context& ctx) noexcept { return ctx.begin(); }
-	auto format(const tl::identifier<T, invalid_value, Tag>& id, std::format_context& ctx) const
+	auto format(const tl::identifier<T, Tag>& id, std::format_context& ctx) const
 	{
 		return format_to(ctx.out(), "{}", id.value());
 	}
 };
 
-template<typename T, T invalid_value, typename Tag>
-struct eastl::hash<tl::identifier<T, invalid_value, Tag>>
+template<typename T, typename Tag>
+struct eastl::hash<tl::identifier<T, Tag>>
 {
-	size_t operator()(tl::identifier<T, invalid_value, Tag> const& id) const
+	size_t operator()(tl::identifier<T, Tag> const& id) const
 	{
 		return hash<T>()(id.value());
 	}