Struct pyo3::types::PySequence[−][src]

#[repr(transparent)]
pub struct PySequence(_);
Expand description

Represents a reference to a Python object supporting the sequence protocol.

Implementations

Returns the number of objects in sequence.

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

Returns whether the sequence is empty.

Returns the concatenation of self and other.

This is equivalent to the Python expression self + other.

Returns the result of repeating a sequence object count times.

This is equivalent to the Python expression self * count. NB: Python accepts negative counts; it returns an empty Sequence.

Concatenates self and other in place.

This is equivalent to the Python statement self += other.

Repeats the sequence object count times and updates self.

This is equivalent to the Python statement self *= count. NB: Python accepts negative counts; it empties the Sequence.

Returns the indexth element of the Sequence.

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

Returns the slice of sequence object between begin and end.

This is equivalent to the Python expression self[begin:end].

Assigns object item to the ith element of self.

This is equivalent to the Python statement self[i] = v.

Deletes the ith element of self.

This is equivalent to the Python statement del self[i].

Assigns the sequence v to the slice of self from i1 to i2.

This is equivalent to the Python statement self[i1:i2] = v.

Deletes the slice from i1 to i2 from self.

This is equivalent to the Python statement del self[i1:i2].

Returns the number of occurrences of value in self, that is, return the number of keys for which self[key] == value.

Determines if self contains value.

This is equivalent to the Python expression value in self.

Returns the first index i for which self[i] == value.

This is equivalent to the Python expression self.index(value).

Returns a fresh list based on the Sequence.

Returns a fresh tuple based on the Sequence.

Methods from Deref<Target = PyAny>

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());
});

Determines whether this object has the given attribute.

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

Retrieves an attribute value.

This is equivalent to the Python expression self.attr_name.

Sets an attribute value.

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

Deletes an attribute.

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

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(())
})?;

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_opPython expression
CompareOp::Eqself == other
CompareOp::Neself != other
CompareOp::Ltself < other
CompareOp::Leself <= other
CompareOp::Gtself > other
CompareOp::Geself >= 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(())
  })?;

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.

Calls the object.

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

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().

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

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]

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()

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]

Returns whether the object is considered to be true.

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

Returns whether the object is considered to be None.

This is equivalent to the Python expression self is None.

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

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

Gets an item from the collection.

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

Sets a collection item value.

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

Deletes an item from the collection.

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

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.

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

Returns the Python type pointer for this object.

Casts the PyObject to a concrete Python object type.

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

Extracts some type from the Python object.

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

Returns the reference count for the Python object.

Computes the “repr” representation of self.

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

Computes the “str” representation of self.

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

Retrieves the hash code of self.

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

Returns the length of the sequence or mapping.

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

Returns the list of attributes of this object.

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

Checks whether this object is an instance of type T.

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

Trait Implementations

Gets the underlying FFI pointer, returns a borrowed pointer.

Performs the conversion.

Formats the value using the given formatter. Read more

The resulting type after dereferencing.

Dereferences the value.

Formats the value using the given formatter. Read more

Performs the conversion.

Performs the conversion.

Extracts Self from the source PyObject.

Performs the conversion.

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

This method tests for !=.

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

Cast &PyAny to &Self without no type checking. Read more

Cast from a concrete Python object type to PyObject.

Cast from a concrete Python object type to PyObject. With exact type check.

Cast a PyAny to a specific type of PyObject. The caller must have already verified the reference is for this type. Read more

Converts self into a Python object.

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more

Immutably borrows from an owned value. Read more

Mutably borrows from an owned value. Read more

Performs the conversion.

Convert from an arbitrary PyObject. Read more

Convert from an arbitrary borrowed PyObject. Read more

Convert from an arbitrary PyObject or panic. Read more

Convert from an arbitrary PyObject or panic. Read more

Convert from an arbitrary PyObject. Read more

Convert from an arbitrary borrowed PyObject. Read more

Convert from an arbitrary borrowed PyObject. Read more

Convert from an arbitrary borrowed PyObject. Read more

Performs the conversion.

Converts self into a Python object and calls the specified closure on the native FFI pointer underlying the Python object. Read more

Converts the given value to a String. Read more

The type returned in the event of a conversion error.

Performs the conversion.

The type returned in the event of a conversion error.

Performs the conversion.