feat: add type alias InternString for macro intern!

[Stargateur]

No description provided.

[davidhewitt]

Thanks, I can kind of see why this is helpful though I also wonder why this is happening enough that this seems worth having in PyO3 itself rather than user code? It's relatively trivial for this one-liner to be written downstream by those who want it.

[Stargateur]

Thanks, I can kind of see why this is helpful though I also wonder why this is happening enough that this seems worth having in PyO3 itself rather than user code? It's relatively trivial for this one-liner to be written downstream by those who want it.

Well, trivial or not that one line every user will maybe add when pyo3 can do it. that the main purpose of lib, share common code. I see no con to this cause change the return type of intern! would be breaking change anyway. This also add clarity cause the return type of the macro was undocumented.

I need this cause the macro would create a string if I call it from multiple location, so I used function that return the string:

/// Return the interned string "foo".
fn foo(py: Python) -> InternString {
    intern!(py, "foo")
}

was more clear than:

/// Return the interned string "foo".
fn foo(py: Python) -> &pyo3::Bound<PyString> {
    intern!(py, "foo")
}