1 files changed, 1 insertions, 0 deletions
diff --git a/hcalc.h b/hcalc.h
index 44d4cc0..06a8428 100644
--- a/hcalc.h
+++ b/hcalc.h
@@ -63,5 +63,6 @@ void show_value(void);
 void bell(void);
 void copy(void);
 void paste(void);
+int number_is_ok(double n);
 
 #define MAXCHARS 15