fix error: 'optional' in namespace 'std' does not name a template type

2021-06-02 18:09:03 +08:00
parent 7c3cb8506f
commit 50dc88a56c
1 changed files with 2 additions and 0 deletions
@@ -6,6 +6,8 @@

 #include <nlohmann/json_fwd.hpp>

+#include <optional>
+
 namespace nix::fetchers {

 typedef std::variant<std::string, uint64_t, Explicit<bool>> Attr;