Change binop to init value if possible

permchain/channels/binop.py

@@ -19,6 +19,10 @@ class BinaryOperatorAggregate(Generic[Value], BaseChannel[Value, Value, Value]):
     def __init__(self, typ: Type[Value], operator: Callable[[Value, Value], Value]):
         self.typ = typ
         self.operator = operator
+        try:
+            self.value = typ()
+        except Exception:
+            pass
 
     @property
     def ValueType(self) -> Type[Value]:

tests/test_channels.py

@@ -204,8 +204,7 @@ def test_binop() -> None:
         assert channel.ValueType is int
         assert channel.UpdateType is int
 
-        with pytest.raises(EmptyChannelError):
-            channel.get()
+        assert channel.get() == 0
 
         channel.update([1, 2, 3])
         assert channel.get() == 6
@@ -221,8 +220,7 @@ async def test_binop_async() -> None:
         assert channel.ValueType is int
         assert channel.UpdateType is int
 
-        with pytest.raises(EmptyChannelError):
-            channel.get()
+        assert channel.get() == 0
 
         channel.update([1, 2, 3])
         assert channel.get() == 6