but meh
Hello, I'm back again trying to do something very unusual, I want to call python from typescript by going through rust in the middle, however I am having some issues with being unable to load the pyo3 compiled extension inside of nodejs - basically all of the python symbols are missing - is this even possible to resolve? If so what libraries do I have to load explicitly?
(using neon for the rust<->js bridge)
Basically trying to do something like this https://github.com/ISNIT0/Node-Python-FFI but when I load my module in node I am missing all the upstream python symbols
Does anybody have an idea how I can emulate Python's Enums? So far I simply used a ZST with class attributes, but the consumers of my library apparently insisted on constructing the value via a constructor rather than just accessing the class's members. I only need string and usize enums.
alternatively - and I'm not sure whether this would be sufficient - does PyO3 use/support the Into-Traits? In particular I get the error
TypeError: Can't convert <FileType object at 0x7fe7fa782870> to PyString, because I'm trying to assign a class to a field of type string. Can I implement e.g. Into<String> or Into<PyString> to make it work?
Hi everyone! I'm writing a library where I'd like to avoid mutation of a Python object passed from a Rust function to a Python function. Basically, implement the equivalent of
some_python_method(arg.copy()). I've tried, from Rust, calling the PyObject .call_method0('copy') function as well as Rust's .copy() method before passing the PyObject argument to the Python function, but it still ends up mutating the original PyObject. Thought there's maybe something simple I'm missing.
(I don't think PyObject has
copy so I assume you meant clone?)
can you share some more of your code?
@davidhewitt I've made do with class attributes to emulate Python's enums, I think that's enough for my use case.
other than that I'm pretty sure that
.copy() does exactly the same thing as it does in python (because it calls into python).
Thanks @Lehona ! deepcopy was the answer.
@Lehona for enums at the moment we only have
#[derive(FromPyObject)] - if you're interested in helping finish off PyO3/pyo3#1045 I think we're not far from supporting C-style enums more fully. For the FileType object assignment I'm a little confused exactly what you're asking. I think you might be looking for .to_string() from std::string::ToString trait? Just impl Display for FileType? Or maybe if you're wanting PyString to automatically convert to FileType - that's an interesting one, not supported right now. Maybe could open an issue about it? Not sure if we'd want that, implicit conversions are not very Rusty...
but I think class attributes that produce a
FileType are even better anyway!
Is there any way to define a function that works on any 2D array? Right now, I'm converting PyArray2's to ArrayViewMut2's (via "as_array_mut()"), which is OK. But for calls from Rust ndarray, converting to a view [via ".view_mut()"] is annoying. Ideally, the function would also work with Rust [[]]'s, but I can't figure that out at all.
-- Aside: Although I'm motivated by the Python to Rust use case, this is really a ndarray question. Is there a ndarray user forum where I could ask?
-- Aside: Although I'm motivated by the Python to Rust use case, this is really a ndarray question. Is there a ndarray user forum where I could ask?
The best you could do is make a Rust function which is generic on said trait, and then a pyO3
#[pyfunction] which takes PyArray2 argument and then calls the Rust function.
You could try users.rust-lang.org if there's no dedicated
ndarray forum
@reem ^
eg:
pub struct InnerStruct {
pub a: u32,
pub b: u16,
...
pub z: u64,
}
#[pyclass]
pub struct MyWrapperClass {
pub inner: InnerStruct,
}
(also @sr-gi)
@daniil-konovalenko I use this pattern since I'm binding a rust library I do not maintain, so I cannot modify the source of the original library. @Lehona Yeah, this is indeed a simplification, in the real case most of the types are non-primitive, what actually made me realise this may not be as straightforward as I though on first sight, given passing those types to Python require adding the con
version between the native rust type and the wrapped python type.
version between the native rust type and the wrapped python type.
Also, to the best of my knowledge using PyO3 (which is not that extensive tbh), this pattern can be used to allow trait bounds from classes defined in Python. You can define the wrapper class and make it implement a certain trait bound, and then pass a wrapped Python class and use it where a trait bound is required
datetime.timedelta, I think it'd be appropriate?
2 replies
I use pyo3 extensively in py-polars. After compilation of the python library, would it be possible for users (with their own rustc) to compile user defined functions that interchange with my Po3 objects?
Hello, I have a question as a newbie. I've written a function in rust that aims to pretty print some data. That function returns a
While creating the String, I use
PyResult<String>While creating the String, I use
writeln!() to add newline characters. My problem is these are printed as escaped '\n' on the python side. I'd like them to be "decoded" I guess and actually print on the next line.
Ah! Sorry, no issue here! This is only occuring when quickly testing in a python interpreter (and not running print, D'oh!)- running as a python file with a print statement and all is well :D
to get a string like
True rather than true
Something in the spirit of
macro_rules! python_repr {
($x:expr) => {
ToPyObject::to_object($x).__repr__()
}
}