Struct CompressionError

pub struct CompressionError(/* private fields */);

Implementations

impl CompressionError

pub fn new_err<A>(args: A) -> PyErr

where A: PyErrArguments + Send + Sync + 'static,

Creates a new PyErr of this type.

Methods from Deref<Target = PyAny>

pub fn downcast<T>(&self) -> Result<&T, PyDowncastError<'_>>

where T: for<'py> PyTryFrom<'py>,

Converts this PyAny to a concrete Python type.

Examples

use pyo3::prelude::*;
use pyo3::types::{PyAny, PyDict, PyList};

Python::with_gil(|py| {
    let dict = PyDict::new(py);
    assert!(dict.is_instance::<PyAny>().unwrap());
    let any: &PyAny = dict.as_ref();
    assert!(any.downcast::<PyDict>().is_ok());
    assert!(any.downcast::<PyList>().is_err());
});

pub fn hasattr<N>(&self, attr_name: N) -> Result<bool, PyErr>

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) -> Result<&PyAny, PyErr>

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) -> Result<(), PyErr>

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) -> Result<(), PyErr>

where N: ToPyObject,

Deletes an attribute.

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

pub fn compare<O>(&self, other: O) -> Result<Ordering, PyErr>

where O: ToPyObject,

Returns an Ordering between self and other.

This is equivalent to the following Python code:

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

Examples

use pyo3::prelude::*;
use pyo3::types::PyFloat;
use std::cmp::Ordering;

Python::with_gil(|py| -> PyResult<()> {
    let a = PyFloat::new(py, 0_f64);
    let b = PyFloat::new(py, 42_f64);
    assert_eq!(a.compare(b)?, Ordering::Less);
    Ok(())
})?;

It will return PyErr for values that cannot be compared:

use pyo3::prelude::*;
use pyo3::types::{PyFloat, PyString};

Python::with_gil(|py| -> PyResult<()> {
    let a = PyFloat::new(py, 0_f64);
    let b = PyString::new(py, "zero");
    assert!(a.compare(b).is_err());
    Ok(())
})?;

pub fn rich_compare<O>( &self, other: O, compare_op: CompareOp, ) -> Result<&PyAny, PyErr>

where O: ToPyObject,

Tests whether two Python objects obey a given CompareOp.

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

compare_op	Python expression
CompareOp::Eq	self == other
CompareOp::Ne	self != other
CompareOp::Lt	self < other
CompareOp::Le	self <= other
CompareOp::Gt	self > other
CompareOp::Ge	self >= other

Examples

use pyo3::prelude::*;
use pyo3::types::PyInt;
use pyo3::class::basic::CompareOp;

Python::with_gil(|py| -> PyResult<()> {
    let a: &PyInt = 0_u8.into_py(py).into_ref(py).downcast()?;
    let b: &PyInt = 42_u8.into_py(py).into_ref(py).downcast()?;
    assert!(a.rich_compare(b, CompareOp::Le)?.is_true()?);
    Ok(())
  })?;

pub fn is_callable(&self) -> bool

Determines whether this object appears callable.

This is equivalent to Python’s callable() function.

Examples

use pyo3::prelude::*;

Python::with_gil(|py| -> PyResult<()> {
       let builtins = PyModule::import(py, "builtins")?;
       let print = builtins.getattr("print")?;
       assert!(print.is_callable());
       Ok(())
})?;

This is equivalent to the Python statement assert callable(print).

Note that unless an API needs to distinguish between callable and non-callable objects, there is no point in checking for callability. Instead, it is better to just do the call and handle potential exceptions.

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

Calls the object.

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

pub fn call0(&self) -> Result<&PyAny, PyErr>

Calls the object without arguments.

This is equivalent to the Python expression self().

Examples

use pyo3::prelude::*;

Python::with_gil(|py| -> PyResult<()> {
    let module = PyModule::import(py, "builtins")?;
    let help = module.getattr("help")?;
    help.call0()?;
    Ok(())
})?;

This is equivalent to the Python expression help().

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

Calls the object with only positional arguments.

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

Examples

use pyo3::prelude::*;

Python::with_gil(|py| -> PyResult<()> {
    let module = PyModule::import(py, "operator")?;
    let add = module.getattr("add")?;
    let args = (1,2);
    let value = add.call1(args)?;
    assert_eq!(value.extract::<i32>()?, 3);
    Ok(())
})?;

This is equivalent to the following Python code:

from operator import add

value = add(1,2)
assert value == 3

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

Calls a method on the object.

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

Examples

use pyo3::prelude::*;
use pyo3::types::{PyDict, PyList};
use crate::pyo3::types::IntoPyDict;

Python::with_gil(|py| -> PyResult<()> {
    let list = PyList::new(py, vec![3, 6, 5, 4, 7]);
    let kwargs = vec![("reverse", true)].into_py_dict(py);

    list.call_method("sort", (), Some(kwargs))?;
    assert_eq!(list.extract::<Vec<i32>>()?, vec![7, 6, 5, 4, 3]);
    Ok(())
})?;

This is equivalent to the following Python code:

my_list = [3, 6, 5, 4, 7]
my_list.sort(reverse = True)
assert my_list == [7, 6, 5, 4, 3]

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

Calls a method on the object without arguments.

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

Examples

use pyo3::prelude::*;
use pyo3::types::PyFloat;
use std::f64::consts::PI;

Python::with_gil(|py| -> PyResult<()> {
    let pi = PyFloat::new(py, PI);
    let ratio = pi.call_method0("as_integer_ratio")?;
    let (a, b) = ratio.extract::<(u64, u64)>()?;
    assert_eq!(a, 884_279_719_003_555);
    assert_eq!(b, 281_474_976_710_656);
    Ok(())
})?;

This is equivalent to the following Python code:

import math

a, b = math.pi.as_integer_ratio()

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

Calls a method on the object with only positional arguments.

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

Examples

use pyo3::prelude::*;
use pyo3::types::PyList;

Python::with_gil(|py| -> PyResult<()> {
    let list = PyList::new(py, vec![1, 3, 4]);
    list.call_method1("insert", (1, 2))?;
    assert_eq!(list.extract::<Vec<u8>>()?, [1, 2, 3, 4]);
    Ok(())
})?;

This is equivalent to the following Python code:

list_ = [1,3,4]
list_.insert(1,2)
assert list_ == [1,2,3,4]

pub fn is_true(&self) -> Result<bool, PyErr>

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) -> Result<bool, PyErr>

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) -> Result<&PyAny, PyErr>

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) -> Result<(), PyErr>

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) -> Result<(), PyErr>

where K: ToBorrowedObject,

Deletes an item from the collection.

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

pub fn iter(&self) -> Result<&PyIterator, PyErr>

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<'a>>

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) -> Result<D, PyErr>

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) -> Result<&PyString, PyErr>

Computes the “repr” representation of self.

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

pub fn str(&self) -> Result<&PyString, PyErr>

Computes the “str” representation of self.

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

pub fn hash(&self) -> Result<isize, PyErr>

Retrieves the hash code of self.

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

pub fn len(&self) -> Result<usize, PyErr>

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>(&self) -> Result<bool, PyErr>

where T: PyTypeObject,

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 CompressionError

fn as_ptr(&self) -> *mut PyObject

Gets the underlying FFI pointer, returns a borrowed pointer.

impl AsRef<PyAny> for CompressionError

fn as_ref(&self) -> &PyAny

Converts this type into a shared reference of the (usually inferred) input type.

impl Debug for CompressionError

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

Formats the value using the given formatter.

impl Deref for CompressionError

type Target = PyAny

The resulting type after dereferencing.

fn deref(&self) -> &PyAny

Dereferences the value.

impl Display for CompressionError

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

Formats the value using the given formatter.

impl Error for CompressionError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

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

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

Converts to this type from the input type.

impl From<&CompressionError> for Py<CompressionError>

fn from(other: &CompressionError) -> Self

Converts to this type from the input type.

impl From<&CompressionError> for PyErr

fn from(err: &CompressionError) -> PyErr

Converts to this type from the input type.

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

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

Extracts Self from the source PyObject.

impl IntoPy<Py<CompressionError>> for &CompressionError

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

Performs the conversion.

impl PartialEq for CompressionError

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

Tests for self and other values to be equal, and is used by ==.

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

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PyNativeType for CompressionError

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

Returns a GIL marker constrained to the lifetime of this type.

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

Cast &PyAny to &Self without no type checking.

impl PyTypeInfo for CompressionError

const NAME: &'static str = "CompressionError"

Class name.

const MODULE: Option<&'static str>

Module name, if any.

type AsRefTarget = CompressionError

Utility type to make Py::as_ref work.

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

PyTypeObject instance for this type.

fn is_type_of(object: &PyAny) -> bool

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

fn is_exact_type_of(object: &PyAny) -> bool

Checks if object is an instance of this type.

impl ToPyObject for CompressionError

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

Converts self into a Python object.