Crate slice_group_by

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Crate slice-group-by is a library for efficiently iterating on a slice by groups defined by a function that specifies if two elements are in the same group.

Example: Linear Searched Immutable Groups

You will only need to define a function that returns true if two elements are in the same group.

The LinearGroupBy iterator will always gives contiguous elements to the predicate function.

use slice_group_by::GroupBy;

let slice = &[1, 1, 1, 3, 3, 2, 2, 2];

let mut iter = slice.linear_group_by_key(|x| -x);

assert_eq!(iter.next(), Some(&[1, 1, 1][..]));
assert_eq!(iter.next(), Some(&[3, 3][..]));
assert_eq!(iter.next(), Some(&[2, 2, 2][..]));
assert_eq!(iter.next(), None);

Example: Linear Searched Immutable Str Slices

You will only need to define a function that returns true if two char are in the same group.

The LinearStrGroupBy iterator will always gives contiguous char to the predicate function.

use slice_group_by::StrGroupBy;

let string = "aaaabbbbb饰饰cccc";

let mut iter = string.linear_group_by(|a, b| a == b);

assert_eq!(iter.next(), Some("aaaa"));
assert_eq!(iter.next(), Some("bbbbb"));
assert_eq!(iter.next(), Some("饰饰"));
assert_eq!(iter.next(), Some("cccc"));
assert_eq!(iter.next(), None);

Example: Binary Searched Mutable Groups

It is also possible to get mutable non overlapping groups of a slice.

The BinaryGroupBy/Mut and ExponentialGroupBy/Mut iterators will not necessarily gives contiguous elements to the predicate function. The predicate function should implement an order consistent with the sort order of the slice.

use slice_group_by::GroupByMut;

let slice = &mut [1, 1, 1, 2, 2, 2, 3, 3];

let mut iter = slice.binary_group_by_mut(|a, b| a == b);

assert_eq!(iter.next(), Some(&mut [1, 1, 1][..]));
assert_eq!(iter.next(), Some(&mut [2, 2, 2][..]));
assert_eq!(iter.next(), Some(&mut [3, 3][..]));
assert_eq!(iter.next(), None);

Example: Exponential Searched Mutable Groups starting from the End

It is also possible to get mutable non overlapping groups of a slice even starting from the end of it.

use slice_group_by::GroupByMut;

let slice = &mut [1, 1, 1, 2, 2, 2, 3, 3];

let mut iter = slice.exponential_group_by_mut(|a, b| a == b).rev();

assert_eq!(iter.next(), Some(&mut [3, 3][..]));
assert_eq!(iter.next(), Some(&mut [2, 2, 2][..]));
assert_eq!(iter.next(), Some(&mut [1, 1, 1][..]));
assert_eq!(iter.next(), None);

Structs

BinaryGroup
An iterator that will return non-overlapping groups of equal elements, according to the PartialEq::eq function in the slice using binary search.
BinaryGroupBy
An iterator that will return non-overlapping groups in the slice using binary search.
BinaryGroupByKey
An iterator that will return non-overlapping groups in the slice using binary search.
BinaryGroupByKeyMut
An iterator that will return non-overlapping mutable groups in the slice using binary search.
BinaryGroupByMut
An iterator that will return non-overlapping mutable groups in the slice using binary search.
BinaryGroupMut
An iterator that will return non-overlapping mutable groups of equal elements, according to the PartialEq::eq function in the slice using binary search.
ExponentialGroup
An iterator that will return non-overlapping groups of equal elements, according to the PartialEq::eq function in the slice using exponential search.
ExponentialGroupBy
An iterator that will reutrn non-overlapping groups in the slice using exponential search.
ExponentialGroupByKey
An iterator that will reutrn non-overlapping groups in the slice using exponential search.
ExponentialGroupByKeyMut
An iterator that will reutrn non-overlapping mutable groups in the slice using exponential search.
ExponentialGroupByMut
An iterator that will reutrn non-overlapping mutable groups in the slice using exponential search.
ExponentialGroupMut
An iterator that will return non-overlapping mutable groups of equal elements, according to the PartialEq::eq function in the slice using exponential search.
LinearGroup
An iterator that will return non-overlapping groups of equal elements in the slice using linear/sequential search.
LinearGroupBy
LinearGroupByKey
An iterator that will return non-overlapping groups of equal elements in the slice using linear/sequential search.
LinearGroupByKeyMut
An iterator that will return non-overlapping mutable groups in the slice using linear/sequential search.
LinearGroupByMut
LinearGroupMut
An iterator that will return non-overlapping mutable groups of equal elements in the slice using linear/sequential search.
LinearStrGroup
An iterator that will return non-overlapping groups of equal char in the str using linear/sequential search.
LinearStrGroupBy
An iterator that will return non-overlapping groups in the str using linear/sequential search.
LinearStrGroupByKey
An iterator that will return non-overlapping groups in the str using linear/sequential search.
LinearStrGroupByKeyMut
An iterator that will return non-overlapping mutable groups in the str using linear/sequential search.
LinearStrGroupByMut
An iterator that will return non-overlapping mutable groups in the str using linear/sequential search.
LinearStrGroupMut
An iterator that will return non-overlapping mutable groups of equal char in the str using linear/sequential search.

Traits

GroupBy
A convenient trait to construct an iterator returning non-overlapping groups defined by a predicate.
GroupByMut
A convenient trait to construct an iterator returning non-overlapping mutable groups defined by a predicate.
StrGroupBy
A convenient trait to construct an iterator returning non-overlapping str slices defined by a predicate.
StrGroupByMut
A convenient trait to construct an iterator returning non-overlapping mutable str slices defined by a predicate.

Functions

exponential_search
Exponential searches this sorted slice for a given element.
exponential_search_by
Binary searches this sorted slice with a comparator function.
exponential_search_by_key
Binary searches this sorted slice with a key extraction function.