Added associative container constructor to `object`

Added `is_associative_container`, `is_map`, `is_unordered_map`
TODO: add tests

src/common/app_parameters.cpp

@@ -122,17 +122,11 @@ object app_parameters::as_object() const {
 		return object{};
 	}
 
-	// Transform m_values into appropriate map type; TODO: add helper to object for this
-	std::map<std::string, object> values_map;
-	for (auto& value : m_values) {
-		values_map.emplace(value.first, value.second);
-	}
-
 	return std::map<std::string, object>{
 		{ "Path", m_path },
 		{ "Args", m_args },
 		{ "Switches", m_switches },
-		{ "Values", values_map }
+		{ "Values", m_values }
 	};
 }
 

src/include/object.hpp

@@ -71,8 +71,9 @@ public:
 	};
 
 	template<typename T>
-	struct is_backing<T, typename std::enable_if<std::is_same<T, map_t>::value>::type> {
-		static constexpr bool value = true;
+	struct is_backing<T, typename std::enable_if<is_associative_container<T>::value>::type> {
+		static constexpr bool value = std::is_same<typename is_associative_container<T>::key_type, std::string>::value
+			&& std::is_same<typename is_associative_container<T>::value_type, object>::value;
 		using type = map_t;
 	};
 
@@ -97,7 +98,8 @@ public:
 	// Value constructors
 	template<typename T,
 		typename std::enable_if<is_backing<typename std::decay<T>::type>::value
-		&& !is_sequence_container<typename std::decay<T>::type>::value>::type* = nullptr>
+		&& !is_sequence_container<typename std::decay<T>::type>::value
+		&& (!is_associative_container<typename std::decay<T>::type>::value || std::is_same<typename remove_cvref<T>::type, map_t>::value)>::type* = nullptr>
 	object(T&& in_value)
 		: m_value{ typename is_backing<typename std::decay<T>::type>::type{ std::forward<T>(in_value) } } {
 		// Empty ctor body
@@ -124,6 +126,30 @@ public:
 		}
 	}
 
+	// std::unordered_map<std::string, object>
+	template<typename T,
+		typename std::enable_if<is_unordered_map<typename std::decay<T>::type>::value
+			&& std::is_same<typename is_unordered_map<typename std::decay<T>::type>::key_type, std::string>::value
+			&& std::is_same<typename is_unordered_map<typename std::decay<T>::type>::value_type, object>::value>::type* = nullptr>
+	object(T&& in_value)
+		: m_value{ map_t{ in_value.begin(), in_value.end() } } {
+		// Empty ctor body
+	}
+
+	// Non-map_t associative containers (container<std::string, T>)
+	template<typename T,
+		typename std::enable_if<is_associative_container<typename remove_cvref<T>::type>::value
+			&& (std::is_convertible<typename is_associative_container<typename remove_cvref<T>::type>::key_type, std::string>::value
+			|| std::is_convertible<typename is_associative_container<typename remove_cvref<T>::type>::key_type, std::string_view>::value)
+			&& !std::is_same<typename is_associative_container<typename remove_cvref<T>::type>::value_type, object>::value>::type* = nullptr>
+	object(T&& in_value)
+		: m_value{ map_t{} } {
+		auto& map = std::get<map_t>(m_value);
+		for (auto& pair : in_value) {
+			map.emplace(pair.first, pair.second);
+		}
+	}
+
 	object(const char* in_str);
 	object(const std::string_view& in_str);
 

src/include/type_traits.hpp

@@ -30,6 +30,13 @@
 
 namespace jessilib {
 
+/** remove_cvref (can be replaced with C++20) */
+
+template<class T>
+struct remove_cvref {
+	typedef std::remove_cv_t<std::remove_reference_t<T>> type;
+};
+
 /** is_vector */
 
 template<typename T>
@@ -108,7 +115,7 @@ struct is_unordered_set<std::unordered_set<T>> {
 	constexpr bool operator()() const noexcept { return true; }
 };
 
-/** is_unordered_set */
+/** is_unordered_multiset */
 
 template<typename T>
 struct is_unordered_multiset : std::false_type {};
@@ -121,6 +128,57 @@ struct is_unordered_multiset<std::unordered_multiset<T>> {
 	constexpr bool operator()() const noexcept { return true; }
 };
 
+/** is_map */
+
+template<typename T>
+struct is_map : std::false_type {};
+
+template<typename KeyT, typename ValueT>
+struct is_map<std::map<KeyT, ValueT>> {
+	using key_type = KeyT;
+	using value_type = ValueT;
+	static constexpr bool value{ true };
+	constexpr operator bool() const noexcept { return true; }
+	constexpr bool operator()() const noexcept { return true; }
+};
+
+/** is_unordered_map */
+
+template<typename T>
+struct is_unordered_map : std::false_type {};
+
+template<typename KeyT, typename ValueT>
+struct is_unordered_map<std::unordered_map<KeyT, ValueT>> {
+	using key_type = KeyT;
+	using value_type = ValueT;
+	static constexpr bool value{ true };
+	constexpr operator bool() const noexcept { return true; }
+	constexpr bool operator()() const noexcept { return true; }
+};
+
+/** is_associative_container */
+
+template<typename T>
+struct is_associative_container : std::false_type {};
+
+template<typename KeyT, typename ValueT>
+struct is_associative_container<std::map<KeyT, ValueT>> {
+	using key_type = KeyT;
+	using value_type = ValueT;
+	static constexpr bool value{ true };
+	constexpr operator bool() const noexcept { return true; }
+	constexpr bool operator()() const noexcept { return true; }
+};
+
+template<typename KeyT, typename ValueT>
+struct is_associative_container<std::unordered_map<KeyT, ValueT>> {
+	using key_type = KeyT;
+	using value_type = ValueT;
+	static constexpr bool value{ true };
+	constexpr operator bool() const noexcept { return true; }
+	constexpr bool operator()() const noexcept { return true; }
+};
+
 /** is_sequence_container */
 
 template<typename T>