diff --git a/bin/_blackbox_common.sh b/bin/_blackbox_common.sh
index b886ad8..9915c8d 100755
--- a/bin/_blackbox_common.sh
+++ b/bin/_blackbox_common.sh
@@ -14,7 +14,7 @@
 
 
 # If $EDITOR is not set, set it to "vi":
-: ${EDITOR:-vi} ;
+: ${EDITOR:=vi} ;
 
  
 # Outputs a string that is the base directory of this VCS repo.