README: adjust boost::optional example

The "from_json" example for boost::optional is not complete and should also handle the 'none' case.
2026-07-29 15:13:04 +04:00 · 2017-01-29 02:46:58 +00:00
parent f642934b18
commit f2873e6d3a
1 changed files with 3 additions and 1 deletions
@@ -563,7 +563,9 @@ namespace nlohmann {
        }

        static void from_json(const json& j, boost::optional<T>& opt) {
-            if (!j.is_null()) {
+            if (j.is_null()) {
+                opt = boost::none;
+            } else {
                opt = j.get<T>(); // same as above, but with 
                                  // adl_serializer<T>::from_json
            }