[ox/std] Remove dedicated keys array from SmallMap

deps/ox/src/ox/std/smallmap.hpp

@@ -17,20 +17,19 @@
 
 namespace ox {
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz = 0>
 class SmallMap {
 
 	public:
 		using key_t = K;
 		using value_t = T;
-
-	private:
 		struct Pair {
 			K key = {};
 			T value{};
 		};
-		using PairVector = Vector<Pair>;
+
-		Vector<K> m_keys;
+	private:
+		using PairVector = Vector<Pair, SmallSz>;
 		PairVector m_pairs;
 
 	public:
@@ -63,7 +62,22 @@ class SmallMap {
 		constexpr std::size_t size() const noexcept;
 
 		[[nodiscard]]
-		constexpr Vector<K> const&keys() const noexcept;
+		constexpr Vector<K> keys() const noexcept;
+
+		[[nodiscard]]
+		constexpr K const&key(size_t i) const noexcept;
+
+		[[nodiscard]]
+		constexpr T const&value(size_t i) const noexcept;
+
+		[[nodiscard]]
+		constexpr T &value(size_t i) noexcept;
+
+		[[nodiscard]]
+		constexpr Pair const&get(size_t i) const noexcept;
+
+		[[nodiscard]]
+		constexpr Pair &get(size_t i) noexcept;
 
 		constexpr void clear();
 
@@ -76,58 +90,46 @@ class SmallMap {
 
 };
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr SmallMap<K, T>::SmallMap(SmallMap<K, T> const&other) {
+constexpr SmallMap<K, T, SmallSz>::SmallMap(SmallMap<K, T, SmallSz> const&other) {
 	m_pairs = other.m_pairs;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr SmallMap<K, T>::SmallMap(SmallMap<K, T> &&other) noexcept {
+constexpr SmallMap<K, T, SmallSz>::SmallMap(SmallMap<K, T, SmallSz> &&other) noexcept {
-	m_keys = std::move(other.m_keys);
 	m_pairs = std::move(other.m_pairs);
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr SmallMap<K, T>::~SmallMap() {
+constexpr SmallMap<K, T, SmallSz>::~SmallMap() {
 	clear();
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr bool SmallMap<K, T>::operator==(SmallMap const&other) const {
+constexpr bool SmallMap<K, T, SmallSz>::operator==(SmallMap const&other) const {
-	if (m_keys != other.m_keys) {
+	return m_pairs == other.m_pairs;
-		return false;
-	}
-	for (int i = 0; i < m_keys.size(); ++i) {
-		auto &k = m_keys[i];
-		if (at(k) != other.at(k)) {
-			return false;
-		}
-	}
-	return true;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr SmallMap<K, T> &SmallMap<K, T>::operator=(SmallMap<K, T> const&other) {
+constexpr SmallMap<K, T, SmallSz> &SmallMap<K, T, SmallSz>::operator=(SmallMap<K, T, SmallSz> const&other) {
 	if (this != &other) {
 		clear();
-		m_keys = other.m_keys;
 		m_pairs = other.m_pairs;
 	}
 	return *this;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr SmallMap<K, T> &SmallMap<K, T>::operator=(SmallMap<K, T> &&other) noexcept {
+constexpr SmallMap<K, T, SmallSz> &SmallMap<K, T, SmallSz>::operator=(SmallMap<K, T, SmallSz> &&other) noexcept {
 	if (this != &other) {
 		clear();
-		m_keys = std::move(other.m_keys);
 		m_pairs = std::move(other.m_pairs);
 	}
 	return *this;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr T &SmallMap<K, T>::operator[](MaybeView_t<K> const&k) {
+constexpr T &SmallMap<K, T, SmallSz>::operator[](MaybeView_t<K> const&k) {
 	bool isNew{};
 	auto p = &access(m_pairs, k, isNew);
 	if (isNew) {
@@ -136,8 +138,8 @@ constexpr T &SmallMap<K, T>::operator[](MaybeView_t<K> const&k) {
 	return p->value;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr Result<T*> SmallMap<K, T>::at(MaybeView_t<K> const&k) noexcept {
+constexpr Result<T*> SmallMap<K, T, SmallSz>::at(MaybeView_t<K> const&k) noexcept {
 	auto p = access(m_pairs, k);
 	if (!p) {
 		return {nullptr, OxError(1, "value not found for given key")};
@@ -145,8 +147,8 @@ constexpr Result<T*> SmallMap<K, T>::at(MaybeView_t<K> const&k) noexcept {
 	return &p->value;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr Result<const T*> SmallMap<K, T>::at(MaybeView_t<K> const&k) const noexcept {
+constexpr Result<const T*> SmallMap<K, T, SmallSz>::at(MaybeView_t<K> const&k) const noexcept {
 	auto p = access(m_pairs, k);
 	if (!p) {
 		return {nullptr, OxError(1, "value not found for given key")};
@@ -154,8 +156,8 @@ constexpr Result<const T*> SmallMap<K, T>::at(MaybeView_t<K> const&k) const noex
 	return &p->value;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr void SmallMap<K, T>::erase(MaybeView_t<K> const&k) {
+constexpr void SmallMap<K, T, SmallSz>::erase(MaybeView_t<K> const&k) {
 	size_t i{};
 	for (auto const&p : m_pairs) {
 		if (k == p.key) {
@@ -164,32 +166,61 @@ constexpr void SmallMap<K, T>::erase(MaybeView_t<K> const&k) {
 		++i;
 	}
 	std::ignore = m_pairs.erase(i);
-	std::ignore = m_keys.erase(i);
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr bool SmallMap<K, T>::contains(MaybeView_t<K> const&k) const noexcept {
+constexpr bool SmallMap<K, T, SmallSz>::contains(MaybeView_t<K> const&k) const noexcept {
 	return access(m_pairs, k) != nullptr;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr std::size_t SmallMap<K, T>::size() const noexcept {
+constexpr std::size_t SmallMap<K, T, SmallSz>::size() const noexcept {
-	return m_keys.size();
+	return m_pairs.size();
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr Vector<K> const&SmallMap<K, T>::keys() const noexcept {
+constexpr Vector<K> SmallMap<K, T, SmallSz>::keys() const noexcept {
-	return m_keys;
+	ox::Vector<K> keys;
+	keys.reserve(m_pairs.size());
+	for (auto const&p : m_pairs) {
+		keys.emplace_back(p.key);
+	}
+	return keys;
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
-constexpr void SmallMap<K, T>::clear() {
+constexpr K const&SmallMap<K, T, SmallSz>::key(size_t i) const noexcept {
+	return m_pairs[i].key;
+}
+
+template<typename K, typename T, size_t SmallSz>
+constexpr T const&SmallMap<K, T, SmallSz>::value(size_t i) const noexcept {
+	return m_pairs[i].value;
+}
+
+template<typename K, typename T, size_t SmallSz>
+constexpr T &SmallMap<K, T, SmallSz>::value(size_t i) noexcept {
+	return m_pairs[i].value;
+}
+
+template<typename K, typename T, size_t SmallSz>
+constexpr SmallMap<K, T, SmallSz>::Pair const&SmallMap<K, T, SmallSz>::get(size_t i) const noexcept {
+	return m_pairs[i];
+}
+
+template<typename K, typename T, size_t SmallSz>
+constexpr SmallMap<K, T, SmallSz>::Pair &SmallMap<K, T, SmallSz>::get(size_t i) noexcept {
+	return m_pairs[i];
+}
+
+template<typename K, typename T, size_t SmallSz>
+constexpr void SmallMap<K, T, SmallSz>::clear() {
 	m_pairs.clear();
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
 template<typename KK>
-constexpr typename SmallMap<K, T>::Pair const&SmallMap<K, T>::access(
+constexpr typename SmallMap<K, T, SmallSz>::Pair const&SmallMap<K, T, SmallSz>::access(
 		PairVector const&pairs, KK const&k, bool &isNew) const {
 	for (auto const&p : pairs) {
 		if (p.key == k) {
@@ -198,13 +229,12 @@ constexpr typename SmallMap<K, T>::Pair const&SmallMap<K, T>::access(
 		}
 	}
 	isNew = true;
-	m_keys.emplace_back(K(k));
 	return pairs.emplace_back();
 }
 
-template<typename K, typename T>
+template<typename K, typename T, size_t SmallSz>
 template<typename KK>
-constexpr typename SmallMap<K, T>::Pair &SmallMap<K, T>::access(
+constexpr typename SmallMap<K, T, SmallSz>::Pair &SmallMap<K, T, SmallSz>::access(
 		PairVector &pairs, KK const&k, bool &isNew) {
 	for (auto &p : pairs) {
 		if (p.key == k) {
@@ -213,7 +243,6 @@ constexpr typename SmallMap<K, T>::Pair &SmallMap<K, T>::access(
 		}
 	}
 	isNew = true;
-	m_keys.emplace_back(K(k));
 	return pairs.emplace_back();
 }