Add missing header

john-z-yang · Dec 10, 2023 · 68a5c0f · 68a5c0f
1 parent 34d2b03
commit 68a5c0f
Showing 1 changed file with 1 addition and 0 deletions.
diff --git a/src/sexpr/Casting.hpp b/src/sexpr/Casting.hpp
@@ -5,6 +5,7 @@
 #include "SExpr.hpp"
 #include <functional>
 #include <memory>
+#include <optional>
 #include <sstream>
 
 namespace sexpr {