René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Deserialize dataclass as Rust struct/mapping","articleBody":"Hi, thanks for the great crate! I'm using it to deserialize things that I can't easily wrap with `#[derive(FromPyObject)]`, but that are `serde` compatible. On the Python side, I'm using dataclasses a lot, and I'd like to convert them to Rust structs. So I have something like this on the Rust side:\n\n```rust\n#[derive(serde::Deserialize)] // This can't use FromPyObject\nstruct Foo {\n    a: i32,\n}\n\n#[pyfunction]\nfn take_foo\u003c's\u003e(py: Python, arg: \u0026Bound\u003c's, PyAny\u003e) {\n    pythonize::depythonize::\u003cFoo\u003e(arg).unwrap();\n} \n```\n\nand I'd like to send something like this from the Python side:\n```python\n@dataclasses.dataclass\nclass Foo:\n    a: int\n\nffi.take_foo(Foo(a=1))\n```\n\nHowever, currently that ends with an error:\n```\npyo3_runtime.PanicException: called `Result::unwrap()` on an `Err` value: UnexpectedType(\"'Foo' object cannot be converted to 'Mapping'\")\n```\n\nIs there a way to make it work? I can pre-convert the dataclass to a dictionary with `dataclasses.as_dict(Foo(a=1))`, but that seems wasteful. `FromPyObject` is able to read the fields of the object, even if it is not a dictionary, so it seems like `depythonize` could also do that.\n\nThanks for your answer!","author":{"url":"https://github.com/Kobzol","@type":"Person","name":"Kobzol"},"datePublished":"2025-08-28T14:21:44.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/93/pythonize/issues/93"}