Compile errors with 0.21.1

[nickdrozd]

Bug Description

Updated to 0.21.1, now getting several of this error:

error[E0624]: associated constant `_PYO3_DEF` is private
  --> src/lib.rs:25:1
   |
25 | #[pymodule]
   | ^^^^^^^^^^^ private associated constant

This is using declarative modules. I assume it's related to #4009. Compiling with 0.21.0 works fine.

Steps to Reproduce

mod whatever;

use pyo3::prelude::*;

#[pymodule]
mod rust_stuff {
    #[pymodule_export]
    use crate::whatever::SomePyClass;
}

Backtrace

No response

Your operating system and version

Ubuntu

Your Python version (python --version)

3.12

Your Rust version (rustc --version)

rustc 1.79.0-nightly (5f2c7d2bf 2024-03-25)

Your PyO3 version

0.21.1

How did you install python? Did you use a virtualenv?

...

Additional Info

No response

[alex]

If you add pub(crate) on that class, does it work?

…

On Tue, Apr 2, 2024, 2:11 PM Nick Drozd ***@***.***> wrote: Bug Description Updated to 0.21.1, now getting several of this error: error[E0624]: associated constant `_PYO3_DEF` is private --> src/lib.rs:25:1 | 25 | #[pymodule] | ^^^^^^^^^^^ private associated constant This is using declarative modules. I assume it's related to #4009 <#4009>. Compiling with 0.21.0 works fine. Steps to Reproduce mod whatever; use pyo3::prelude::*; #[pymodule] mod rust_stuff { #[pymodule_export] use crate::whatever::SomePyClass; } Backtrace *No response* Your operating system and version Ubuntu Your Python version (python --version) 3.12 Your Rust version (rustc --version) rustc 1.79.0-nightly (5f2c7d2bf 2024-03-25) Your PyO3 version 0.21.1 How did you install python? Did you use a virtualenv? ... Additional Info *No response* — Reply to this email directly, view it on GitHub <#4036>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAAAGBE2VAV4CUMVR2V3R5LY3LYE5AVCNFSM6AAAAABFT3T2NWVHI2DSMVQWIX3LMV43ASLTON2WKOZSGIZDCMJTGIZTSNQ> . You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[nickdrozd]

pub(crate) doesn't work, nor do other variations of pub.

The errors are coming both from #[pyclass] on pub struct and from create_exception!(mod_name, Whatever, PyException).

[davidhewitt]

Yep this makes sense, in #4009 when I added the constants I didn't think about visibility. Should be a relatively easy fix, I will get to it by the end of the week if nobody else fancies taking a bite at this sooner.

[alecandido]

In case anyone arrives here, and it needs a workaround for v0.21.1 (current latest published release), wrapping the class in the other file (or non-pythonified module) in a further module makes it accessible.

use pyo3::prelude::*;

mod othermod {
    use pyo3::prelude::*;

    #[pymodule]
    pub mod wrapper {
        use pyo3::prelude::*;

        #[pyclass]
        pub struct Struct;
    }
}

#[pymodule]
mod myext {
    #[pymodule_export]
    use super::othermod::wrapper;
}

Ok, having this extra wrapper around is definitely less than ideal, but for me makes it acceptable to start using the declarative feature to experiment myself, waiting for a proper fix.

[nickdrozd]

In 0.21.1 I was getting 7 compile errors, 3 from #[pyclass] and 4 from create_exception!.

In 0.21.2 the #[pyclass] errors are fixed, but I'm stil getting the 4 create_exception! errors.

Exceptions are created like this:

// rules.rs

create_exception!(rules, UnknownRule, PyException);

Then exported like this:

// lib.rs

mod rules;

#[pymodule]
mod rust_stuff {
    #[pymodule_export]
    use crate::rules::UnknownRule;
}

Error looks like:

error[E0624]: associated constant `_PYO3_DEF` is private
  --> src/lib.rs:31:1
   |
31 | #[pymodule]
   | ^^^^^^^^^^^ private associated constant
   |
  ::: src/rules.rs:12:1
   |
12 | create_exception!(rules, UnknownRule, PyException);
   | -------------------------------------------------- private associated constant defined here

If there is a better way to create exceptions, I would be happy to switch to that.

[Icxolu]

Thanks for reporting! I have opened #4086 which should fix it.