Serialize empty tuple into instead of null

codenut · codenut · commit 1aa1039f975f · 2025-01-13T20:34:52.000+09:00
Signed-off-by: Michael Valladolid &lt;mikevalladolid@gmail.com&gt;
diff --git a/include/nlohmann/detail/conversions/to_json.hpp b/include/nlohmann/detail/conversions/to_json.hpp
@@ -426,6 +426,13 @@ inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<
     j = { std::get<Idx>(t)... };
 }
 
+template<typename BasicJsonType, typename Tuple>
+inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& /*unused*/, index_sequence<> /*unused*/)
+{
+    using array_t = typename BasicJsonType::array_t;
+    j = array_t();
+}
+
 template<typename BasicJsonType, typename T, enable_if_t<is_constructible_tuple<BasicJsonType, T>::value, int > = 0>
 inline void to_json(BasicJsonType& j, const T& t)
 {
diff --git a/single_include/nlohmann/json.hpp b/single_include/nlohmann/json.hpp
@@ -5987,6 +5987,13 @@ inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<
     j = { std::get<Idx>(t)... };
 }
 
+template<typename BasicJsonType, typename Tuple>
+inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& /*unused*/, index_sequence<> /*unused*/)
+{
+    using array_t = typename BasicJsonType::array_t;
+    j = array_t();
+}
+
 template<typename BasicJsonType, typename T, enable_if_t<is_constructible_tuple<BasicJsonType, T>::value, int > = 0>
 inline void to_json(BasicJsonType& j, const T& t)
 {

Original file line number	Diff line number	Diff line change
`@@ -426,6 +426,13 @@ inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<`
`426`	`426`	`j = { std::get<Idx>(t)... };`
`427`	`427`	`}`
`428`	`428`
	`429`	`+template<typename BasicJsonType, typename Tuple>`
	`430`	`+inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& /unused/, index_sequence<> /unused/)`
	`431`	`+{`
	`432`	`+ using array_t = typename BasicJsonType::array_t;`
	`433`	`+ j = array_t();`
	`434`	`+}`
	`435`	`+`
`429`	`436`	`template<typename BasicJsonType, typename T, enable_if_t<is_constructible_tuple<BasicJsonType, T>::value, int > = 0>`
`430`	`437`	`inline void to_json(BasicJsonType& j, const T& t)`
`431`	`438`	`{`
Original file line number	Diff line number	Diff line change
`@@ -5987,6 +5987,13 @@ inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& t, index_sequence<`
`5987`	`5987`	`j = { std::get<Idx>(t)... };`
`5988`	`5988`	`}`
`5989`	`5989`
	`5990`	`+template<typename BasicJsonType, typename Tuple>`
	`5991`	`+inline void to_json_tuple_impl(BasicJsonType& j, const Tuple& /unused/, index_sequence<> /unused/)`
	`5992`	`+{`
	`5993`	`+ using array_t = typename BasicJsonType::array_t;`
	`5994`	`+ j = array_t();`
	`5995`	`+}`
	`5996`	`+`
`5990`	`5997`	`template<typename BasicJsonType, typename T, enable_if_t<is_constructible_tuple<BasicJsonType, T>::value, int > = 0>`
`5991`	`5998`	`inline void to_json(BasicJsonType& j, const T& t)`
`5992`	`5999`	`{`