1 files changed, 4 insertions, 0 deletions
diff --git a/ink_stroke_modeler/types.h b/ink_stroke_modeler/types.h
index 922c0f7..cc77565 100644
--- a/ink_stroke_modeler/types.h
+++ b/ink_stroke_modeler/types.h
@@ -20,6 +20,8 @@
 #include <cmath>
 #include <ostream>
 
+#include "absl/status/status.h"
+
 namespace ink {
 namespace stroke_model {
 
@@ -148,6 +150,8 @@ bool operator!=(const Input &lhs, const Input &rhs);
 std::ostream &operator<<(std::ostream &s, Input::EventType event_type);
 std::ostream &operator<<(std::ostream &s, const Input &input);
 
+absl::Status ValidateInput(const Input &input);
+
 // A modeled input produced by the stroke modeler.
 struct Result {
   // The position and velocity of the stroke tip.