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

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

A Python iterator object.

Examples

use pyo3::prelude::*;

Python::with_gil(|py| -> PyResult<()> {
    let list = py.eval("iter([1, 2, 3, 4])", None, None)?;
    let numbers: PyResult<Vec<usize>> = list
        .iter()?
        .map(|i| i.and_then(PyAny::extract::<usize>))
        .collect();
    let sum: usize = numbers?.iter().sum();
    assert_eq!(sum, 10);
    Ok(())
})

Implementations

Constructs a PyIterator from a Python iterable object.

Equivalent to Python’s built-in iter function.

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

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::{IntoPyDict, PyList};

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).

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

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.

Retrieves the next item from an iterator.

Returns None when the iterator is exhausted. If an exception occurs, returns Some(Err(..)). Further next() calls after an exception occurs are likely to repeatedly result in the same exception.

The type of the elements being iterated over.

Returns the bounds on the remaining length of the iterator. Read more

Consumes the iterator, counting the number of iterations and returning it. Read more

Consumes the iterator, returning the last element. Read more

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

recently added

Advances the iterator by n elements. Read more

Returns the nth element of the iterator. Read more

Creates an iterator starting at the same point, but stepping by the given amount at each iteration. Read more

Takes two iterators and creates a new iterator over both in sequence. Read more

‘Zips up’ two iterators into a single iterator of pairs. Read more

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

recently added

Creates a new iterator which places a copy of separator between adjacent items of the original iterator. Read more

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

recently added

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator. Read more

Takes a closure and creates an iterator which calls that closure on each element. Read more

Calls a closure on each element of an iterator. Read more

Creates an iterator which uses a closure to determine if an element should be yielded. Read more

Creates an iterator that both filters and maps. Read more

Creates an iterator which gives the current iteration count as well as the next value. Read more

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information. Read more

Creates an iterator that skips elements based on a predicate. Read more

Creates an iterator that yields elements based on a predicate. Read more

Creates an iterator that both yields elements based on a predicate and maps. Read more

Creates an iterator that skips the first n elements. Read more

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner. Read more

An iterator adapter similar to fold that holds internal state and produces a new iterator. Read more

Creates an iterator that works like map, but flattens nested structure. Read more

Creates an iterator that flattens nested structure. Read more

Creates an iterator which ends after the first None. Read more

Does something with each element of an iterator, passing the value on. Read more

Borrows an iterator, rather than consuming it. Read more

Transforms an iterator into a collection. Read more

Consumes an iterator, creating two collections from it. Read more

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

new API

Reorders the elements of this iterator in-place according to the given predicate, such that all those that return true precede all those that return false. Returns the number of true elements found. Read more

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

new API

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false. Read more

An iterator method that applies a function as long as it returns successfully, producing a single, final value. Read more

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error. Read more

Folds every element into an accumulator by applying an operation, returning the final result. Read more

Reduces the elements to a single one, by repeatedly applying a reducing operation. Read more

Tests if every element of the iterator matches a predicate. Read more

Tests if any element of the iterator matches a predicate. Read more

Searches for an element of an iterator that satisfies a predicate. Read more

Applies function to the elements of iterator and returns the first non-none result. Read more

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

new API

Applies function to the elements of iterator and returns the first true result or the first error. Read more

Searches for an element in an iterator, returning its index. Read more

Searches for an element in an iterator from the right, returning its index. Read more

Returns the maximum element of an iterator. Read more

Returns the minimum element of an iterator. Read more

Returns the element that gives the maximum value from the specified function. Read more

Returns the element that gives the maximum value with respect to the specified comparison function. Read more

Returns the element that gives the minimum value from the specified function. Read more

Returns the element that gives the minimum value with respect to the specified comparison function. Read more

Reverses an iterator’s direction. Read more

Converts an iterator of pairs into a pair of containers. Read more

Creates an iterator which copies all of its elements. Read more

Creates an iterator which clones all of its elements. Read more

Repeats an iterator endlessly. Read more

Sums the elements of an iterator. Read more

Iterates over the entire iterator, multiplying all the elements Read more

Lexicographically compares the elements of this Iterator with those of another. Read more

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

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function. Read more

Lexicographically compares the elements of this Iterator with those of another. Read more

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

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function. Read more

Determines if the elements of this Iterator are equal to those of another. Read more

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

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function. Read more

Determines if the elements of this Iterator are unequal to those of another. Read more

Determines if the elements of this Iterator are lexicographically less than those of another. Read more

Determines if the elements of this Iterator are lexicographically less or equal to those of another. Read more

Determines if the elements of this Iterator are lexicographically greater than those of another. Read more

Determines if the elements of this Iterator are lexicographically greater than or equal to those of another. Read more

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

new API

Checks if the elements of this iterator are sorted. Read more

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

new API

Checks if the elements of this iterator are sorted using the given comparator function. Read more

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

new API

Checks if the elements of this iterator are sorted using the given key extraction function. Read more

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.