From ac756f99109b9dc233f71d9f8d9dd7539ac57de0 Mon Sep 17 00:00:00 2001
From: Fabian Zills <fzills@icp.uni-stuttgart.de>
Date: Fri, 18 Oct 2024 17:47:39 +0200
Subject: [PATCH 1/2] draft

---
 znflow/base.py    | 8 +++++++-
 znflow/dynamic.py | 4 ++--
 2 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/znflow/base.py b/znflow/base.py
index 3f0b0bd..1db3cf5 100644
--- a/znflow/base.py
+++ b/znflow/base.py
@@ -12,6 +12,12 @@
     from znflow.graph import DiGraph
 
 
+class _NOT_RESVOLED_TYPE:
+    pass
+
+NOT_RESVOLED = _NOT_RESVOLED_TYPE()
+
+
 @contextlib.contextmanager
 def disable_graph(*args, **kwargs):
     """Temporarily disable set the graph to empty.
@@ -354,7 +360,7 @@ class FunctionFuture(NodeBaseMixin):
     kwargs: typing.Dict
     item: any = None
 
-    result: any = dataclasses.field(default=None, init=False, repr=True)
+    result: any = dataclasses.field(default=NOT_RESVOLED, init=False, repr=True)
 
     _protected_ = NodeBaseMixin._protected_ + ["function", "args", "kwargs"]
 
diff --git a/znflow/dynamic.py b/znflow/dynamic.py
index 75d1b7b..f290776 100644
--- a/znflow/dynamic.py
+++ b/znflow/dynamic.py
@@ -1,6 +1,6 @@
 import typing as t
 
-from znflow.base import Connection, disable_graph, get_graph, FunctionFuture
+from znflow.base import Connection, disable_graph, get_graph, FunctionFuture, NOT_RESVOLED
 
 
 def resolve(value: t.Union[Connection, t.Any]) -> t.Any:
@@ -25,7 +25,7 @@ def resolve(value: t.Union[Connection, t.Any]) -> t.Any:
     # get the actual value
     with disable_graph():
         result = value.result
-    if result is not None:
+    if result is not NOT_RESVOLED:
         return result
     # we assume, that if the result is None, the node has not been run yet
     graph = get_graph()

From dfcf9759ad28b7fc495fcb71f3f36d4aa54ac22e Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Fri, 18 Oct 2024 15:51:16 +0000
Subject: [PATCH 2/2] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 znflow/base.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/znflow/base.py b/znflow/base.py
index 1db3cf5..1d7cc05 100644
--- a/znflow/base.py
+++ b/znflow/base.py
@@ -15,6 +15,7 @@
 class _NOT_RESVOLED_TYPE:
     pass
 
+
 NOT_RESVOLED = _NOT_RESVOLED_TYPE()