diff --git a/src/structs.h b/src/structs.h
index 4520e76..eb86e48 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -917,6 +917,8 @@
 # define CSF_SILENT	0x1000	// "emsg_silent" reset by ":try"
 // Note that CSF_ELSE is only used when CSF_TRY and CSF_WHILE are unset
 // (an ":if"), and CSF_SILENT is only used when CSF_TRY is set.
+//
+#define CSF_FUNC_DEF	0x2000	// a function was defined in this block
 
 /*
  * What's pending for being reactivated at the ":endtry" of this try