copy when flipping function type

CQCL · Jun 18, 2024 · e10b1d1 · e10b1d1
1 parent 80e6832
commit e10b1d1
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/hugr-py/src/hugr/_tys.py b/hugr-py/src/hugr/_tys.py
@@ -238,7 +238,7 @@ def empty(cls) -> FunctionType:
         return cls(input=[], output=[])
 
     def flip(self) -> FunctionType:
-        return FunctionType(input=self.output, output=self.input)
+        return FunctionType(input=list(self.output), output=list(self.input))
 
 
 @dataclass(frozen=True)