Added fix for when two restrictions are satisfied with the same word.

luscenje_struktur/component.py

@@ -109,6 +109,8 @@ class Component:
             for tr in to_ret:
                 # make sure that one word is not used twice in same to_ret
                 new_to_ret.extend([{**dict(tr), **m} for m in cmatch if any([m_v not in dict(tr).values() for m_v in m.values()])])
+            if len(new_to_ret) == 0:
+                return None
             to_ret = new_to_ret
             del new_to_ret