From 47fefc39df1cc7791c707802178e67e391aee989 Mon Sep 17 00:00:00 2001
From: Helmut Merz <helmutm@cy55.de>
Date: Sat, 10 Mar 2012 11:43:44 +0100
Subject: [PATCH] ignore predicate interface on import also when empty string

---
 external/element.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/external/element.py b/external/element.py
index 5c48146..1490dd2 100644
--- a/external/element.py
+++ b/external/element.py
@@ -93,7 +93,7 @@ class ConceptElement(Element):
         formState = self.getInstance().applyTemplate(data=kw, ignoreValidation=True)
         # simple hack for resolving interface definition:
         pi = self.get('predicateInterface')
-        if pi is not None:
+        if pi:
             adapted(self.object).predicateInterface = resolve(pi)
 
     def getInstance(self, omit=['title']):