Struct im::hashset::HashSet

pub struct HashSet<A, S = RandomState> { /* fields omitted */ }

A hash set.

An immutable hash set.

This is implemented as a HashMap with no values, so it shares the exact performance characteristics of HashMap.

Methods

impl<A> HashSet<A, RandomState> where
    A: Hash + Eq, 

pub fn new() -> Self

Construct an empty set.

pub fn singleton<R>(a: R) -> Self where
    R: Shared<A>, 

Construct a set with a single value.

Examples

let set = HashSet::singleton(123);
assert!(set.contains(&123));

impl<A, S> HashSet<A, S>

pub fn is_empty(&self) -> bool

Test whether a set is empty.

Time: O(1)

Examples

assert!(
  !hashset![1, 2, 3].is_empty()
);
assert!(
  HashSet::<i32>::new().is_empty()
);

pub fn len(&self) -> usize

Get the size of a set.

Time: O(1)

Examples

assert_eq!(3, hashset![1, 2, 3].len());

impl<A, S> HashSet<A, S> where
    A: Hash + Eq,
    S: BuildHasher, 

pub fn with_hasher<RS>(hasher: RS) -> Self where
    RS: Shared<S>, 

Construct an empty hash set using the provided hasher.

pub fn new_from<A1>(&self) -> HashSet<A1, S> where
    A1: Hash + Eq, 

Construct an empty hash set using the same hasher as the current hash set.

pub fn iter(&self) -> Iter<Arc<A>>

Get an iterator over the values in a hash set.

Please note that the order is consistent between sets using the same hasher, but no other ordering guarantee is offered. Items will not come out in insertion order or sort order. They will, however, come out in the same order every time for the same set.

pub fn insert<R>(&self, a: R) -> Self where
    R: Shared<A>, 

Insert a value into a set.

Time: O(log n)

Examples

let set = hashset![123];
assert_eq!(
  set.insert(456),
  hashset![123, 456]
);

pub fn insert_mut<R>(&mut self, a: R) where
    R: Shared<A>, 

Insert a value into a set.

This is a copy-on-write operation, so that the parts of the set's structure which are shared with other sets will be safely copied before mutating.

Time: O(log n)

pub fn contains<BA: ?Sized>(&self, a: &BA) -> bool where
    BA: Hash + Eq,
    A: Borrow<BA>, 

Test if a value is part of a set.

Time: O(log n)

pub fn remove<BA: ?Sized>(&self, a: &BA) -> Self where
    BA: Hash + Eq,
    A: Borrow<BA>, 

Remove a value from a set if it exists.

Time: O(log n)

pub fn remove_mut<BA: ?Sized>(&mut self, a: &BA) where
    BA: Hash + Eq,
    A: Borrow<BA>, 

Remove a value from a set if it exists.

This is a copy-on-write operation, so that the parts of the set's structure which are shared with other sets will be safely copied before mutating.

Time: O(log n)

pub fn union<RS>(&self, other: RS) -> Self where
    RS: Borrow<Self>, 

Construct the union of two sets.

pub fn unions<I>(i: I) -> Self where
    I: IntoIterator<Item = Self>,
    S: Default, 

Construct the union of multiple sets.

pub fn difference<RS>(&self, other: RS) -> Self where
    RS: Borrow<Self>, 

Construct the difference between two sets.

pub fn intersection<RS>(&self, other: RS) -> Self where
    RS: Borrow<Self>, 

Construct the intersection of two sets.

pub fn is_subset<RS>(&self, other: RS) -> bool where
    RS: Borrow<Self>, 

Test whether a set is a subset of another set, meaning that all values in our set must also be in the other set.

pub fn is_proper_subset<RS>(&self, other: RS) -> bool where
    RS: Borrow<Self>, 

Test whether a set is a proper subset of another set, meaning that all values in our set must also be in the other set. A proper subset must also be smaller than the other set.

Trait Implementations

impl<A: Hash + Eq + Ord, S: BuildHasher> From<HashSet<A, S>> for OrdSet<A>

fn from(hashset: HashSet<A, S>) -> Self

Performs the conversion.

impl<'a, A: Hash + Eq + Ord, S: BuildHasher> From<&'a HashSet<A, S>> for OrdSet<A>

fn from(hashset: &HashSet<A, S>) -> Self

Performs the conversion.

impl<A, S> Clone for HashSet<A, S>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<A: Hash + Eq, S: BuildHasher + Default> PartialEq for HashSet<A, S>

fn eq(&self, other: &Self) -> 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 !=.

impl<A: Hash + Eq, S: BuildHasher + Default> Eq for HashSet<A, S>

impl<A: Hash + Eq + PartialOrd, S: BuildHasher + Default> PartialOrd for HashSet<A, S>

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

This method tests less than (for self and other) and is used by the < operator.

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

This method tests less than or equal to (for self and other) and is used by the <= operator.

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

This method tests greater than (for self and other) and is used by the > operator.

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

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl<A: Hash + Eq + Ord, S: BuildHasher + Default> Ord for HashSet<A, S>

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

impl<A: Hash + Eq, S: BuildHasher + Default> Hash for HashSet<A, S>

fn hash<H>(&self, state: &mut H) where
    H: Hasher, 

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where
    H: Hasher, 

Feeds a slice of this type into the given [Hasher].

impl<A: Hash + Eq, S: BuildHasher + Default> Default for HashSet<A, S>

fn default() -> Self

Returns the "default value" for a type.

impl<A: Hash + Eq, S: BuildHasher> Add for HashSet<A, S>

type Output = HashSet<A, S>

The resulting type after applying the + operator.

fn add(self, other: Self) -> Self::Output

Performs the + operation.

impl<A: Hash + Eq, S: BuildHasher> Mul for HashSet<A, S>

type Output = HashSet<A, S>

The resulting type after applying the * operator.

fn mul(self, other: Self) -> Self::Output

Performs the * operation.

impl<'a, A: Hash + Eq, S: BuildHasher> Add for &'a HashSet<A, S>

type Output = HashSet<A, S>

The resulting type after applying the + operator.

fn add(self, other: Self) -> Self::Output

Performs the + operation.

impl<'a, A: Hash + Eq, S: BuildHasher> Mul for &'a HashSet<A, S>

type Output = HashSet<A, S>

The resulting type after applying the * operator.

fn mul(self, other: Self) -> Self::Output

Performs the * operation.

impl<A, S> Sum for HashSet<A, S> where
    A: Hash + Eq,
    S: BuildHasher + Default, 

fn sum<I>(it: I) -> Self where
    I: Iterator<Item = Self>, 

Method which takes an iterator and generates Self from the elements by "summing up" the items.

impl<A, S, R> Extend<R> for HashSet<A, S> where
    A: Hash + Eq,
    S: BuildHasher,
    R: Shared<A>, 

fn extend<I>(&mut self, iter: I) where
    I: IntoIterator<Item = R>, 

Extends a collection with the contents of an iterator.

impl<A: Hash + Eq + Debug, S: BuildHasher + Default> Debug for HashSet<A, S>

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

Formats the value using the given formatter.

impl<A: Hash + Eq, RA, S> FromIterator<RA> for HashSet<A, S> where
    RA: Shared<A>,
    S: BuildHasher + Default, 

fn from_iter<T>(i: T) -> Self where
    T: IntoIterator<Item = RA>, 

Creates a value from an iterator.

impl<'a, A: Hash + Eq, S: BuildHasher> IntoIterator for &'a HashSet<A, S>

type Item = Arc<A>

The type of the elements being iterated over.

type IntoIter = Iter<Self::Item>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<A: Hash + Eq, S: BuildHasher> IntoIterator for HashSet<A, S>

type Item = Arc<A>

The type of the elements being iterated over.

type IntoIter = Iter<Self::Item>

Which kind of iterator are we turning this into?

fn into_iter(self) -> Self::IntoIter

Creates an iterator from a value.

impl<'s, 'a, A: ?Sized, OA, SA, SB> From<&'s HashSet<&'a A, SA>> for HashSet<OA, SB> where
    A: ToOwned<Owned = OA> + Hash + Eq,
    OA: Borrow<A> + Hash + Eq,
    SA: BuildHasher,
    SB: BuildHasher + Default, 

fn from(set: &HashSet<&A, SA>) -> Self

Performs the conversion.

impl<'a, A: Hash + Eq + Clone, S: BuildHasher + Default> From<&'a [A]> for HashSet<A, S>

fn from(slice: &'a [A]) -> Self

Performs the conversion.

impl<'a, A: Hash + Eq, S: BuildHasher + Default> From<&'a [Arc<A>]> for HashSet<A, S>

fn from(slice: &'a [Arc<A>]) -> Self

Performs the conversion.

impl<A: Hash + Eq, S: BuildHasher + Default> From<Vec<A>> for HashSet<A, S>

fn from(vec: Vec<A>) -> Self

Performs the conversion.

impl<'a, A: Hash + Eq + Clone, S: BuildHasher + Default> From<&'a Vec<A>> for HashSet<A, S>

fn from(vec: &Vec<A>) -> Self

Performs the conversion.

impl<'a, A: Hash + Eq, S: BuildHasher + Default> From<&'a Vec<Arc<A>>> for HashSet<A, S>

fn from(vec: &Vec<Arc<A>>) -> Self

Performs the conversion.

impl<A: Eq + Hash, S: BuildHasher + Default> From<HashSet<A>> for HashSet<A, S>

fn from(hash_set: HashSet<A>) -> Self

Performs the conversion.

impl<'a, A: Eq + Hash + Clone, S: BuildHasher + Default> From<&'a HashSet<A>> for HashSet<A, S>

fn from(hash_set: &HashSet<A>) -> Self

Performs the conversion.

impl<'a, A: Eq + Hash, S: BuildHasher + Default> From<&'a HashSet<Arc<A>>> for HashSet<A, S>

fn from(hash_set: &HashSet<Arc<A>>) -> Self

Performs the conversion.

impl<A: Hash + Eq, S: BuildHasher + Default> From<BTreeSet<A>> for HashSet<A, S>

fn from(btree_set: BTreeSet<A>) -> Self

Performs the conversion.

impl<'a, A: Hash + Eq + Clone, S: BuildHasher + Default> From<&'a BTreeSet<A>> for HashSet<A, S>

fn from(btree_set: &BTreeSet<A>) -> Self

Performs the conversion.

impl<'a, A: Hash + Eq, S: BuildHasher + Default> From<&'a BTreeSet<Arc<A>>> for HashSet<A, S>

fn from(btree_set: &BTreeSet<Arc<A>>) -> Self

Performs the conversion.

impl<A: Ord + Hash + Eq, S: BuildHasher + Default> From<OrdSet<A>> for HashSet<A, S>

fn from(ordset: OrdSet<A>) -> Self

Performs the conversion.

impl<'a, A: Ord + Hash + Eq, S: BuildHasher + Default> From<&'a OrdSet<A>> for HashSet<A, S>

fn from(ordset: &OrdSet<A>) -> Self

Performs the conversion.