Crate `itertools`

Extra iterator adaptors, functions and macros.

To extend Iterator with methods in this crate, import the Itertools trait:

# #[allow(unused_imports)]
use itertools::Itertools;

Now, new methods like interleave are available on all iterators:

use itertools::Itertools;

let it = (1..3).interleave(vec![-1, -2]);
itertools::assert_equal(it, vec![1, -1, 2, -2]);

Most iterator methods are also provided as functions (with the benefit that they convert parameters using IntoIterator):

use itertools::interleave;

for elt in interleave(&[1, 2, 3], &[2, 3, 4]) {
    /* loop body */
    # let _ = elt;
}

Crate Features

use_std
- Enabled by default.
- Disable to compile itertools using #![no_std]. This disables any item that depend on allocations (see the use_alloc feature) and hash maps (like unique, counts, into_grouping_map and more).
use_alloc
- Enabled by default.
- Enables any item that depend on allocations (like chunk_by, kmerge, join and many more).

This version of itertools requires Rust 1.63.0 or later.

structs The concrete iterator types.
traits Traits helpful for using certain Itertools methods in generic contexts.

Diff A type returned by the diff_with function.
Either
EitherOrBoth Value that either holds a single A or B, or both.
FoldWhile An enum used for controlling the execution of fold_while.
MinMaxResult MinMaxResult is an enum returned by minmax.
Position The first component of the value yielded by WithPosition. Indicates the position of this element in the iterator results.

Itertools An Iterator blanket implementation that provides extra adaptors and methods.
MultiUnzip An iterator that can be unzipped into multiple collections.
PeekingNext An iterator that allows peeking at an element before deciding to accept it.

assert_equal Assert that two iterables produce equal sequences, with the same semantics as equal(a, b).
concat Combine all an iterator's elements into one element by using Extend.
cons_tuples Create an iterator that maps for example iterators of ((A, B), C) to (A, B, C).
diff_with Compares every element yielded by both i and j with the given function in lock-step and returns a Diff which describes how j differs from i.
equal Return true if both iterables produce equal sequences (elements pairwise equal and sequences of the same length), false otherwise.
iterate Creates a new iterator that infinitely applies function to value and yields results.
kmerge_by Create an iterator that merges elements of the contained iterators.
multiunzip Converts an iterator of tuples into a tuple of containers.
multizip An iterator that generalizes .zip() and allows running multiple iterators in lockstep.
partition Partition a sequence using predicate pred so that elements that map to true are placed before elements which map to false.
process_results “Lift” a function of the values of an iterator so that it can process an iterator of Result values instead.
repeat_n Create an iterator that produces n repetitions of element.
unfold Creates a new unfold source with the specified closure as the "iterator function" and an initial state to eventually pass to the closure