From 5a63864c540421c725544dc9f02df07e6132796d Mon Sep 17 00:00:00 2001
From: yihong0618 <zouzou0208@gmail.com>
Date: Thu, 23 Sep 2021 14:55:57 +0800
Subject: [PATCH] fix: #2973

---
 python/taichi/lang/field.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/python/taichi/lang/field.py b/python/taichi/lang/field.py
index 29a2d11de19c3..c5827c477eff9 100644
--- a/python/taichi/lang/field.py
+++ b/python/taichi/lang/field.py
@@ -187,6 +187,8 @@ def __getitem__(self, key):
     def __str__(self):
         if impl.inside_kernel():
             return self.__repr__()  # make pybind11 happy, see Matrix.__str__
+        if self.snode.ptr is None:
+            return '<Field: Definition of this field is incomplete>'
         else:
             return str(self.to_numpy())