Trait pyo3::conversion::AsPyPointer

source ·

pub unsafe trait AsPyPointer {
    // Required method
    fn as_ptr(&self) -> *mut PyObject;
}

Expand description

Returns a borrowed pointer to a Python object.

The returned pointer will be valid for as long as self is. It may be null depending on the implementation.

§Examples

use pyo3::prelude::*;
use pyo3::types::PyString;
use pyo3::ffi;

Python::with_gil(|py| {
    let s: Py<PyString> = "foo".into_py(py);
    let ptr = s.as_ptr();

    let is_really_a_pystring = unsafe { ffi::PyUnicode_CheckExact(ptr) };
    assert_eq!(is_really_a_pystring, 1);
});

§Safety

For callers, it is your responsibility to make sure that the underlying Python object is not dropped too early. For example, the following code will cause undefined behavior:

Python::with_gil(|py| {
    let ptr: *mut ffi::PyObject = 0xabad1dea_u32.into_py(py).as_ptr();

    let isnt_a_pystring = unsafe {
        // `ptr` is dangling, this is UB
        ffi::PyUnicode_CheckExact(ptr)
    };
});

This happens because the pointer returned by as_ptr does not carry any lifetime information and the Python object is dropped immediately after the 0xabad1dea_u32.into_py(py).as_ptr() expression is evaluated. To fix the problem, bind Python object to a local variable like earlier to keep the Python object alive until the end of its scope.

Implementors must ensure this returns a valid pointer to a Python object, which borrows a reference count from &self.

Required Methods§

source

fn as_ptr(&self) -> *mut PyObject

Returns the underlying FFI pointer as a borrowed pointer.

Trait pyo3::conversion::AsPyPointer

§Examples

§Safety

Required Methods§

fn as_ptr(&self) -> *mut PyObject

Implementations on Foreign Types§

impl<T> AsPyPointer for Option<T>where T: AsPyPointer,

fn as_ptr(&self) -> *mut PyObject

Implementors§

impl AsPyPointer for CancelledError

impl AsPyPointer for IncompleteReadError

impl AsPyPointer for InvalidStateError

impl AsPyPointer for LimitOverrunError

impl AsPyPointer for QueueEmpty

impl AsPyPointer for QueueFull

impl AsPyPointer for TimeoutError

impl AsPyPointer for gaierror

impl AsPyPointer for herror

impl AsPyPointer for timeout

impl AsPyPointer for PyArithmeticError

impl AsPyPointer for PyAssertionError

impl AsPyPointer for PyAttributeError

impl AsPyPointer for PyBaseException

impl AsPyPointer for PyBlockingIOError

impl AsPyPointer for PyBrokenPipeError

impl AsPyPointer for PyBufferError

impl AsPyPointer for PyBytesWarning

impl AsPyPointer for PyChildProcessError

impl AsPyPointer for PyConnectionAbortedError

impl AsPyPointer for PyConnectionError

impl AsPyPointer for PyConnectionRefusedError

impl AsPyPointer for PyConnectionResetError

impl AsPyPointer for PyDeprecationWarning

impl AsPyPointer for PyEOFError

impl AsPyPointer for PyEnvironmentError

impl AsPyPointer for PyException

impl AsPyPointer for PyFileExistsError

impl AsPyPointer for PyFileNotFoundError

impl AsPyPointer for PyFloatingPointError

impl AsPyPointer for PyFutureWarning

impl AsPyPointer for PyGeneratorExit

impl AsPyPointer for PyIOError

impl AsPyPointer for PyImportError

impl AsPyPointer for PyImportWarning

impl AsPyPointer for PyIndexError

impl AsPyPointer for PyInterruptedError

impl AsPyPointer for PyIsADirectoryError

impl AsPyPointer for PyKeyError

impl AsPyPointer for PyKeyboardInterrupt

impl AsPyPointer for PyLookupError

impl AsPyPointer for PyMemoryError

impl AsPyPointer for PyModuleNotFoundError

impl AsPyPointer for PyNameError

impl AsPyPointer for PyNotADirectoryError

impl AsPyPointer for PyNotImplementedError

impl AsPyPointer for PyOSError

impl AsPyPointer for PyOverflowError

impl AsPyPointer for PyPendingDeprecationWarning

impl AsPyPointer for PyPermissionError

impl AsPyPointer for PyProcessLookupError

impl AsPyPointer for PyRecursionError

impl AsPyPointer for PyReferenceError

impl AsPyPointer for PyResourceWarning

impl AsPyPointer for PyRuntimeError

impl AsPyPointer for PyRuntimeWarning

impl AsPyPointer for PyStopAsyncIteration

impl AsPyPointer for PyStopIteration

impl AsPyPointer for PySyntaxError

impl AsPyPointer for PySyntaxWarning

impl AsPyPointer for PySystemError

impl AsPyPointer for PySystemExit

impl AsPyPointer for PyTimeoutError

impl AsPyPointer for PyTypeError

impl AsPyPointer for PyUnboundLocalError

impl AsPyPointer for PyUnicodeDecodeError

impl AsPyPointer for PyUnicodeEncodeError

impl AsPyPointer for PyUnicodeError

impl AsPyPointer for PyUnicodeTranslateError

impl AsPyPointer for PyUnicodeWarning

impl AsPyPointer for PyUserWarning

impl<T> AsPyPointer for Option<T>
where T: AsPyPointer,