How to return a Python list of Union type pyclass objects?

[tushushu]

Hi there,
I would like to implement a read_from_file function as below:

#[pyclass]
pub struct Foo {
    ...
}

#[pyclass]
pub struct Bar {
    ...
}


// Foo and Bar are all pyclasses
enum GenericType {
    FooType(Foo),
    BarType(Bar),
}

#[pyclass]
pub struct GenericWrapper{
    inner: GenericType,
}

#[pyfunction]
pub fn read_from_file(path: &str) -> Vec<GenericWrapper> {
    ...
}

_arr = read_from_file(path="somewhere")
arr = [x.extract_as_foo_or_bar() for x in _arr]

It reads contents from a file and return a list of pyclass objects. I tried to use Enum as a wrapper, but I am not sure how to implement the extract_as_foo_or_bar part. Is there any suggestion? Thanks very much~

[birkenfeld]

First question - do you need the GenericWrapper at all? You could just return Vec<PyObject> from read_from_file...

[tushushu]

@birkenfeld It does not have to be a GenericWrapper, I just want to find a way to return a Vec of different pyclasses.

[tushushu]

I use the codes below and it works, thanks very much @birkenfeld

let mut result: Vec<PyObject> = Vec::new();
result.push(a_foo.into_py(py));
result.push(a_bar.into_py(py));