Struct multiset::HashMultiSet

pub struct HashMultiSet<K> { /* private fields */ }

A hash-based multiset.

Implementations

impl<K> HashMultiSet<K>where
    K: Eq + Hash,

pub fn new() -> Self

Creates a new empty HashMultiSet.

Examples

use multiset::HashMultiSet;

let multiset: HashMultiSet<char> = HashMultiSet::new();

pub fn iter(&self) -> Iter<'_, K>

An iterator visiting all elements in arbitrary order, including each duplicate. The iterator element type is &'a K.

Examples

use multiset::HashMultiSet;
let mut multiset = HashMultiSet::new();
multiset.insert(0);
multiset.insert(0);
multiset.insert(1);

// Will print in an arbitrary order.
for x in multiset.iter() {
    println!("{}", x);
}
assert_eq!(3, multiset.iter().count());

pub fn is_empty(&self) -> bool

Returns true if the multiset contains no elements.

Examples

use multiset::HashMultiSet;

let mut multiset = HashMultiSet::new();
assert!(multiset.is_empty());
multiset.insert(1);
assert!(!multiset.is_empty());

pub fn contains<Q>(&self, value: &Q) -> boolwhere
    K: Borrow<Q>,
    Q: Hash + Eq + ?Sized,

Returns true if the multiset contains a value.

The value may be any borrowed form of the set’s value type, but Hash and Eq on the borrowed form must match those for the value type.

Examples

use multiset::HashMultiSet;

let set: HashMultiSet<_> = [1, 2, 3].iter().cloned().collect();
assert_eq!(set.contains(&1), true);
assert_eq!(set.contains(&4), false);

pub fn len(&self) -> usize

Counts all the elements, including each duplicate.

Examples

A new empty HashMultiSet with 0 total elements:

use multiset::HashMultiSet;

let multiset: HashMultiSet<char> = HashMultiSet::new();
assert_eq!(0, multiset.len());

A HashMultiSet from vec![1,1,2] has 3 total elements:

use multiset::HashMultiSet;
use std::iter::FromIterator;

let multiset: HashMultiSet<i32> = FromIterator::from_iter(vec![1,1,2]);
assert_eq!(3, multiset.len());

pub fn distinct_elements<'a>(&'a self) -> Keys<'a, K, usize>

Returns all the distinct elements in the HashMultiSet.

Examples

A HashMultiSet from vec![1,1,2] has 2 distinct elements, namely 1 and 2, but not 3:

use multiset::HashMultiSet;
use std::collections::HashSet;
use std::iter::FromIterator;

let multiset: HashMultiSet<i64> = FromIterator::from_iter(vec![1,1,2]);
let distinct = multiset.distinct_elements().collect::<HashSet<_>>();
assert_eq!(2, distinct.len());
assert!(distinct.contains(&1));
assert!(distinct.contains(&2));
assert!(!distinct.contains(&3));

pub fn insert(&mut self, val: K)

Inserts an element.

Examples

Insert 5 into a new HashMultiSet:

use multiset::HashMultiSet;

let mut multiset: HashMultiSet<i32> = HashMultiSet::new();
assert_eq!(0, multiset.count_of(&5));
multiset.insert(5);
assert_eq!(1, multiset.count_of(&5));

pub fn insert_times(&mut self, val: K, n: usize)

Inserts an element n times.

Examples

Insert three 5s into a new HashMultiSet:

use multiset::HashMultiSet;

let mut multiset: HashMultiSet<i32> = HashMultiSet::new();
assert_eq!(0, multiset.count_of(&5));
multiset.insert_times(5,3);
assert_eq!(3, multiset.count_of(&5));

pub fn remove(&mut self, val: &K) -> bool

Remove an element. Removal of a nonexistent element has no effect.

Examples

Remove 5 from a new HashMultiSet:

use multiset::HashMultiSet;

let mut multiset: HashMultiSet<i32> = HashMultiSet::new();
multiset.insert(5);
assert_eq!(1, multiset.count_of(&5));
assert!(multiset.remove(&5));
assert_eq!(0, multiset.count_of(&5));
assert!(!multiset.remove(&5));

pub fn remove_times(&mut self, val: &K, times: usize) -> usize

Remove an element n times. If an element is removed as many or more times than it appears, it is entirely removed from the multiset.

Examples

Remove 5s from a HashMultiSet containing 3 of them.

use multiset::HashMultiSet;

let mut multiset: HashMultiSet<i32> = HashMultiSet::new();
multiset.insert_times(5, 3);
assert!(multiset.count_of(&5) == 3);
assert!(multiset.remove_times(&5, 2) == 2);
assert!(multiset.len() == 1);
assert!(multiset.count_of(&5) == 1);
assert!(multiset.remove_times(&5, 1) == 1);
assert!(multiset.len() == 0);
assert!(multiset.count_of(&5) == 0);
assert!(multiset.remove_times(&5, 1) == 0);
assert!(multiset.count_of(&5) == 0);

pub fn remove_all(&mut self, val: &K)

Remove all of an element from the multiset.

Examples

Remove all 5s from a HashMultiSet containing 3 of them.

use multiset::HashMultiSet;

let mut multiset: HashMultiSet<i32> = HashMultiSet::new();
multiset.insert_times(5,3);
assert!(multiset.count_of(&5) == 3);
multiset.remove_all(&5);
assert!(multiset.count_of(&5) == 0);

pub fn count_of(&self, val: &K) -> usize

Counts the occurrences of val.

Examples

use multiset::HashMultiSet;

let mut multiset: HashMultiSet<u8> = HashMultiSet::new();
multiset.insert(0);
multiset.insert(0);
multiset.insert(1);
multiset.insert(0);
assert_eq!(3, multiset.count_of(&0));
assert_eq!(1, multiset.count_of(&1));

Trait Implementations

impl<T> Add<HashMultiSet<T>> for HashMultiSet<T>where
    T: Eq + Hash + Clone,

fn add(self, rhs: HashMultiSet<T>) -> HashMultiSet<T>

Combine two HashMultiSets by adding the number of each distinct element.

Examples

use multiset::HashMultiSet;
use std::iter::FromIterator;

let lhs: HashMultiSet<isize> = FromIterator::from_iter(vec![1,2,3]);
let rhs: HashMultiSet<isize> = FromIterator::from_iter(vec![1,1,4]);
let combined = lhs + rhs;
assert_eq!(3, combined.count_of(&1));
assert_eq!(1, combined.count_of(&2));
assert_eq!(1, combined.count_of(&3));
assert_eq!(1, combined.count_of(&4));
assert_eq!(0, combined.count_of(&5));

type Output = HashMultiSet<T>

The resulting type after applying the + operator.

impl<K: Clone> Clone for HashMultiSet<K>

fn clone(&self) -> HashMultiSet<K>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<T> Debug for HashMultiSet<T>where
    T: Eq + Hash + Debug,

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

Formats the value using the given formatter.

impl<A> FromIterator<A> for HashMultiSet<A>where
    A: Eq + Hash,

fn from_iter<T>(iterable: T) -> HashMultiSet<A>where
    T: IntoIterator<Item = A>,

Creates a new HashMultiSet from the elements in an iterable.

Examples

Count occurrences of each char in "hello world":

use multiset::HashMultiSet;
use std::iter::FromIterator;

let vals = vec!['h','e','l','l','o',' ','w','o','r','l','d'];
let multiset: HashMultiSet<char> = FromIterator::from_iter(vals);
assert_eq!(1, multiset.count_of(&'h'));
assert_eq!(3, multiset.count_of(&'l'));
assert_eq!(0, multiset.count_of(&'z'));

impl<T> PartialEq<HashMultiSet<T>> for HashMultiSet<T>where
    T: Eq + Hash,

fn eq(&self, other: &HashMultiSet<T>) -> bool

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

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

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

impl<T> Sub<HashMultiSet<T>> for HashMultiSet<T>where
    T: Eq + Hash + Clone,

fn sub(self, rhs: HashMultiSet<T>) -> HashMultiSet<T>

Combine two HashMultiSets by removing elements in the second multiset from the first. As with remove() (and set difference), excess elements in the second multiset are ignored.

Examples

use multiset::HashMultiSet;
use std::iter::FromIterator;

let lhs: HashMultiSet<isize> = FromIterator::from_iter(vec![1,2,3]);
let rhs: HashMultiSet<isize> = FromIterator::from_iter(vec![1,1,4]);
let combined = lhs - rhs;
assert_eq!(0, combined.count_of(&1));
assert_eq!(1, combined.count_of(&2));
assert_eq!(1, combined.count_of(&3));
assert_eq!(0, combined.count_of(&4));

type Output = HashMultiSet<T>

The resulting type after applying the - operator.

impl<T> Eq for HashMultiSet<T>where
    T: Eq + Hash,