Howto implement PyAsPointer for a struct?

help
1

In another project I've defined a struct ValueType:

#[derive(Clone, PartialEq, Debug)]
pub enum ValueType {
    Int(i64),
    Hex(u64),
    Float(f64),
    String(String),
}

In the current project I want to extend this type to support into_py. So I've extended it as follows:

struct PyValueType(ValueType);

impl ToPyObject for PyValueType
{
    fn to_object(&self, py: Python) -> PyObject {
        match self {
            PyValueType(ValueType::Int(v)) => v.into_py(py),
            PyValueType(ValueType::Hex(v)) => v.into_py(py),
            PyValueType(ValueType::Float(v)) => v.into_py(py),
            PyValueType(ValueType::String(v)) => v.into_py(py),
        }
    }
}

If I want to use it in a pyclass:

    fn foo(slf: PyRef<Self>) -> PyResult<PyObject> {
        let gil = Python::acquire_gil();
        let py = gil.python();
        Ok(PyValueType(ValueType::Int(5).clone()).into_py(py))
    }

I get the following error:

the method `into_py` exists for struct `PyValueType`, but its trait bounds were not satisfied

method cannot be called on `PyValueType` due to unsatisfied trait bounds

note: the following trait bounds were not satisfied:
      `PyValueType: pyo3::AsPyPointer`
      which is required by `&PyValueType: pyo3::IntoPy<pyo3::Py<pyo3::PyAny>>`

How can I solve this issue?

2

You're implementing ToPyObject for PyValueType, but the into_py method comes from the IntoPy trait, right? I'm not familiar with pyo3 but that seems like it have might something to do with the problem.

3

You're right. I've replaced into_py with to_object. Now it works.

4

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