Struct pyo3::types::PyByteArray

#[repr(transparent)]
pub struct PyByteArray(_);

Represents a Python bytearray.

Implementations

impl PyByteArray

pub fn new<'p>(py: Python<'p>, src: &[u8]) -> &'p PyByteArray

Creates a new Python bytearray object.

The byte string is initialized by copying the data from the &[u8].

pub fn new_with<F>(
    py: Python<'_>,
    len: usize,
    init: F
) -> PyResult<&PyByteArray> where
    F: FnOnce(&mut [u8]) -> PyResult<()>, 

Creates a new Python bytearray object with an init closure to write its contents. Before calling init the bytearray is zero-initialised.

• If Python raises a MemoryError on the allocation, new_with will return it inside Err.
• If init returns Err(e), new_with will return Err(e).
• If init returns Ok(()), new_with will return Ok(&PyByteArray).

Example

use pyo3::{prelude::*, types::PyByteArray};
Python::with_gil(|py| -> PyResult<()> {
    let py_bytearray = PyByteArray::new_with(py, 10, |bytes: &mut [u8]| {
        bytes.copy_from_slice(b"Hello Rust");
        Ok(())
    })?;
    let bytearray: &[u8] = unsafe { py_bytearray.as_bytes() };
    assert_eq!(bytearray, b"Hello Rust");
    Ok(())
});

pub fn from<'p, I>(py: Python<'p>, src: &'p I) -> PyResult<&'p PyByteArray> where
    I: AsPyPointer, 

Creates a new Python bytearray object from another PyObject that implements the buffer protocol.

pub fn len(&self) -> usize

Gets the length of the bytearray.

pub fn is_empty(&self) -> bool

Checks if the bytearray is empty.

pub fn data(&self) -> *mut u8

Get the start of the buffer containing the contents of the bytearray.

Note that this bytearray object is both shared and mutable, and the backing buffer may be reallocated if the bytearray is resized. This can occur from Python code as well as from Rust via PyByteArray::resize.

As a result, the returned pointer should be dereferenced only if since calling this method no Python code has executed, PyByteArray::resize has not been called.

pub unsafe fn as_bytes(&self) -> &[u8]

Get the contents of this buffer as a slice.

Safety

This bytearray must not be resized or edited while holding the slice.

Safety Detail

This method is equivalent to std::slice::from_raw_parts(self.data(), self.len()), and so all the safety notes of std::slice::from_raw_parts apply here.

In particular, note that this bytearray object is both shared and mutable, and the backing buffer may be reallocated if the bytearray is resized. Mutations can occur from Python code as well as from Rust, via PyByteArray::as_bytes_mut and PyByteArray::resize.

Extreme care should be exercised when using this slice, as the Rust compiler will make optimizations based on the assumption the contents of this slice cannot change. This can easily lead to undefined behavior.

As a result, this slice should only be used for short-lived operations to read this bytearray without executing any Python code, such as copying into a Vec.

pub unsafe fn as_bytes_mut(&self) -> &mut [u8]

Get the contents of this buffer as a mutable slice.

Safety

This slice should only be used for short-lived operations that write to this bytearray without executing any Python code. See the safety note for PyByteArray::as_bytes.

pub fn to_vec(&self) -> Vec<u8>

Copies the contents of the bytearray to a Rust vector.

Example

let bytearray = PyByteArray::new(py, b"Hello World.");
let mut copied_message = bytearray.to_vec();
assert_eq!(b"Hello World.", copied_message.as_slice());

copied_message[11] = b'!';
assert_eq!(b"Hello World!", copied_message.as_slice());

let locals = [("bytearray", bytearray)].into_py_dict(py);
py.run("assert bytearray == b'Hello World.'", None, Some(locals)).unwrap();

pub fn resize(&self, len: usize) -> PyResult<()>

Resizes the bytearray object to the new length len.

Note that this will invalidate any pointers obtained by PyByteArray::data, as well as any (unsafe) slices obtained from PyByteArray::as_bytes and PyByteArray::as_bytes_mut.

Methods from Deref<Target = PyAny>

pub fn downcast<T>(&self) -> Result<&T, PyDowncastError<'_>> where
    for<'py> T: PyTryFrom<'py>, 

Convert this PyAny to a concrete Python type.

pub fn hasattr<N>(&self, attr_name: N) -> PyResult<bool> where
    N: ToPyObject, 

Determines whether this object has the given attribute.

This is equivalent to the Python expression hasattr(self, attr_name).

pub fn getattr<N>(&self, attr_name: N) -> PyResult<&PyAny> where
    N: ToPyObject, 

Retrieves an attribute value.

This is equivalent to the Python expression self.attr_name.

pub fn setattr<N, V>(&self, attr_name: N, value: V) -> PyResult<()> where
    N: ToBorrowedObject,
    V: ToBorrowedObject, 

Sets an attribute value.

This is equivalent to the Python expression self.attr_name = value.

pub fn delattr<N>(&self, attr_name: N) -> PyResult<()> where
    N: ToPyObject, 

Deletes an attribute.

This is equivalent to the Python expression del self.attr_name.

pub fn compare<O>(&self, other: O) -> PyResult<Ordering> where
    O: ToPyObject, 

Compares two Python objects.

This is equivalent to:

if self == other:
    return Equal
elif a < b:
    return Less
elif a > b:
    return Greater
else:
    raise TypeError("PyAny::compare(): All comparisons returned false")

pub fn rich_compare<O>(
    &self,
    other: O,
    compare_op: CompareOp
) -> PyResult<&PyAny> where
    O: ToPyObject, 

Compares two Python objects.

Depending on the value of compare_op, this is equivalent to one of the following Python expressions:

• CompareOp::Eq: self == other
• CompareOp::Ne: self != other
• CompareOp::Lt: self < other
• CompareOp::Le: self <= other
• CompareOp::Gt: self > other
• CompareOp::Ge: self >= other

pub fn is_callable(&self) -> bool

Determines whether this object is callable.

pub fn call(
    &self,
    args: impl IntoPy<Py<PyTuple>>,
    kwargs: Option<&PyDict>
) -> PyResult<&PyAny>

Calls the object.

This is equivalent to the Python expression self(*args, **kwargs).

pub fn call0(&self) -> PyResult<&PyAny>

Calls the object without arguments.

This is equivalent to the Python expression self().

pub fn call1(&self, args: impl IntoPy<Py<PyTuple>>) -> PyResult<&PyAny>

Calls the object with only positional arguments.

This is equivalent to the Python expression self(*args).

pub fn call_method(
    &self,
    name: &str,
    args: impl IntoPy<Py<PyTuple>>,
    kwargs: Option<&PyDict>
) -> PyResult<&PyAny>

Calls a method on the object.

This is equivalent to the Python expression self.name(*args, **kwargs).

Example

use pyo3::types::IntoPyDict;

let gil = Python::acquire_gil();
let py = gil.python();
let list = vec![3, 6, 5, 4, 7].to_object(py);
let dict = vec![("reverse", true)].into_py_dict(py);
list.call_method(py, "sort", (), Some(dict)).unwrap();
assert_eq!(list.extract::<Vec<i32>>(py).unwrap(), vec![7, 6, 5, 4, 3]);

let new_element = 1.to_object(py);
list.call_method(py, "append", (new_element,), None).unwrap();
assert_eq!(list.extract::<Vec<i32>>(py).unwrap(), vec![7, 6, 5, 4, 3, 1]);

pub fn call_method0(&self, name: &str) -> PyResult<&PyAny>

Calls a method on the object without arguments.

This is equivalent to the Python expression self.name().

pub fn call_method1(
    &self,
    name: &str,
    args: impl IntoPy<Py<PyTuple>>
) -> PyResult<&PyAny>

Calls a method on the object with only positional arguments.

This is equivalent to the Python expression self.name(*args).

pub fn is_true(&self) -> PyResult<bool>

Returns whether the object is considered to be true.

This is equivalent to the Python expression bool(self).

pub fn is_none(&self) -> bool

Returns whether the object is considered to be None.

This is equivalent to the Python expression self is None.

pub fn is_empty(&self) -> PyResult<bool>

Returns true if the sequence or mapping has a length of 0.

This is equivalent to the Python expression len(self) == 0.

pub fn get_item<K>(&self, key: K) -> PyResult<&PyAny> where
    K: ToBorrowedObject, 

Gets an item from the collection.

This is equivalent to the Python expression self[key].

pub fn set_item<K, V>(&self, key: K, value: V) -> PyResult<()> where
    K: ToBorrowedObject,
    V: ToBorrowedObject, 

Sets a collection item value.

This is equivalent to the Python expression self[key] = value.

pub fn del_item<K>(&self, key: K) -> PyResult<()> where
    K: ToBorrowedObject, 

Deletes an item from the collection.

This is equivalent to the Python expression del self[key].

pub fn iter(&self) -> PyResult<&PyIterator>

Takes an object and returns an iterator for it.

This is typically a new iterator but if the argument is an iterator, this returns itself.

pub fn get_type(&self) -> &PyType

Returns the Python type object for this object’s type.

pub fn get_type_ptr(&self) -> *mut PyTypeObject

Returns the Python type pointer for this object.

pub fn cast_as<'a, D>(&'a self) -> Result<&'a D, PyDowncastError<'_>> where
    D: PyTryFrom<'a>, 

Casts the PyObject to a concrete Python object type.

This can cast only to native Python types, not types implemented in Rust.

pub fn extract<'a, D>(&'a self) -> PyResult<D> where
    D: FromPyObject<'a>, 

Extracts some type from the Python object.

This is a wrapper function around FromPyObject::extract().

pub fn get_refcnt(&self) -> isize

Returns the reference count for the Python object.

pub fn repr(&self) -> PyResult<&PyString>

Computes the “repr” representation of self.

This is equivalent to the Python expression repr(self).

pub fn str(&self) -> PyResult<&PyString>

Computes the “str” representation of self.

This is equivalent to the Python expression str(self).

pub fn hash(&self) -> PyResult<isize>

Retrieves the hash code of self.

This is equivalent to the Python expression hash(self).

pub fn len(&self) -> PyResult<usize>

Returns the length of the sequence or mapping.

This is equivalent to the Python expression len(self).

pub fn dir(&self) -> &PyList

Returns the list of attributes of this object.

This is equivalent to the Python expression dir(self).

pub fn is_instance<T: PyTypeObject>(&self) -> PyResult<bool>

Checks whether this object is an instance of type T.

This is equivalent to the Python expression isinstance(self, T).

Trait Implementations

impl AsPyPointer for PyByteArray

fn as_ptr(&self) -> *mut PyObject

Gets the underlying FFI pointer, returns a borrowed pointer.

impl AsRef<PyAny> for PyByteArray

fn as_ref(&self) -> &PyAny

Performs the conversion.

impl Debug for PyByteArray

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl Deref for PyByteArray

type Target = PyAny

The resulting type after dereferencing.

fn deref(&self) -> &PyAny

Dereferences the value.

impl Display for PyByteArray

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl From<&'_ PyByteArray> for Py<PyByteArray>

fn from(other: &PyByteArray) -> Self

Performs the conversion.

impl<'a> From<&'a PyByteArray> for &'a PyAny

fn from(ob: &'a PyByteArray) -> Self

Performs the conversion.

impl<'py> FromPyObject<'py> for &'py PyByteArray

fn extract(obj: &'py PyAny) -> PyResult<Self>

Extracts Self from the source PyObject.

impl IntoPy<Py<PyByteArray>> for &PyByteArray

fn into_py(self, py: Python<'_>) -> Py<PyByteArray>

Performs the conversion.

impl PartialEq<PyByteArray> for PyByteArray

fn eq(&self, o: &PyByteArray) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl PyLayout<PyByteArray> for PyObject

const IS_NATIVE_TYPE: bool

fn get_super(&mut self) -> Option<&mut T::BaseLayout>

fn py_init(&mut self, _value: T)

unsafe fn py_drop(&mut self, _py: Python<'_>)

impl PyNativeType for PyByteArray

fn py(&self) -> Python<'_>

unsafe fn unchecked_downcast(obj: &PyAny) -> &Self

Cast &PyAny to &Self without no type checking.

impl PyTypeInfo for PyByteArray

type Type = ()

Type of objects to store in PyObject struct

type BaseType = PyAny

Base class

type Layout = PyObject

Layout

type BaseLayout = PyObject

Layout of Basetype.

type Initializer = PyNativeTypeInitializer<Self>

Initializer for layout

type AsRefTarget = Self

Utility type to make Py::as_ref work

const NAME: &'static str

Class name

const MODULE: Option<&'static str>

Module name, if any

fn type_object_raw(_py: Python<'_>) -> *mut PyTypeObject

PyTypeObject instance for this type.

fn is_type_of(ptr: &PyAny) -> bool

Checks if object is an instance of this type or a subclass of this type.

const DESCRIPTION: &'static str

Class doc string

const FLAGS: usize

Type flags (ie PY_TYPE_FLAG_GC, PY_TYPE_FLAG_WEAKREF)

fn is_exact_type_of(object: &PyAny) -> bool

Checks if object is an instance of this type.

impl ToPyObject for PyByteArray

fn to_object(&self, py: Python<'_>) -> PyObject

Converts self into a Python object.