18119: Refactor is_injective (2)

sagemath · Apr 22, 2021 · e472040 · e472040
1 parent 7a230ac
commit e472040
Showing 1 changed file with 2 additions and 2 deletions.
diff --git a/src/sage/combinat/words/morphism.py b/src/sage/combinat/words/morphism.py
@@ -3209,9 +3209,9 @@ def check(u, v):
                     tails.add(tail)
                     todo.append(tail)
 
-        images = self.images()
-        if any(not x for x in images):
+        if self.is_erasing():
             return False
+        images = self.images()
         tails = set()
         todo = []