enum HasZero { A = 0, B = 1 } enum HasNoZero { A = 1, B = 2 } var has_zero: HasZero # No warning, because the default `0` is valid. var has_no_zero: HasNoZero # Warning, because there is no `0` in the enum. func test(): print(has_zero) print(has_no_zero) # GH-94634. A parameter is either mandatory or has a default value. func test_no_exec(param: HasNoZero) -> void: print(param) # Loop iterator always has a value. for i: HasNoZero in HasNoZero.values(): print(i) match param: # Pattern bind always has a value. var x: print(x)