Struct scc::Bag

pub struct Bag<T, const ARRAY_LEN: usize = DEFAULT_ARRAY_LEN> { /* private fields */ }

Bag is a lock-free concurrent unordered instance container.

Bag is a linearizable concurrent instance container where ARRAY_LEN instances are stored in a fixed-size array, and the rest are managed by its backup container; this makes a Bag especially efficient if the expected number of instances does not exceed ARRAY_LEN.

The maximum value of ARRAY_LEN is limited to usize::BITS / 2 which is the default value, and if a larger value is specified, Bag::new panics.

Implementations

impl<T, const ARRAY_LEN: usize> Bag<T, ARRAY_LEN>

pub fn new() -> Self

Creates a new Bag.

Panics

Panics if the specified ARRAY_LEN value is larger than usize::BITS / 2.

Examples

use scc::Bag;

let bag: Bag<usize, 16> = Bag::new();

pub fn push(&self, val: T)

Pushes an instance of T.

Examples

use scc::Bag;

let bag: Bag<usize> = Bag::default();

bag.push(11);

pub fn pop(&self) -> Option<T>

Pops an instance in the Bag if not empty.

Examples

use scc::Bag;

let bag: Bag<usize> = Bag::default();

bag.push(37);

assert_eq!(bag.pop(), Some(37));
assert!(bag.pop().is_none());

pub fn pop_all<B, F: FnMut(B, T) -> B>(&self, init: B, fold: F) -> B

Pops all the entries at once, and folds them into an accumulator.

Examples

use scc::Bag;

let bag: Bag<usize> = Bag::default();

bag.push(7);
bag.push(17);
bag.push(37);

assert_eq!(bag.pop_all(0, |a, v| a + v), 61);

bag.push(47);
assert_eq!(bag.pop(), Some(47));
assert!(bag.pop().is_none());
assert!(bag.is_empty());

pub fn is_empty(&self) -> bool

Returns true if the Bag is empty.

Examples

use scc::Bag;

let bag: Bag<usize> = Bag::default();
assert!(bag.is_empty());

bag.push(7);
assert!(!bag.is_empty());

assert_eq!(bag.pop(), Some(7));
assert!(bag.is_empty());

pub fn iter_mut(&mut self) -> Accessor<'_, T, ARRAY_LEN>

Iterates over contained instances for modifying them.

Examples

use scc::Bag;

let mut bag: Bag<usize> = Bag::default();

bag.push(3);
bag.push(3);

assert_eq!(bag.iter_mut().count(), 2);
bag.iter_mut().for_each(|e| { *e += 1; });

assert_eq!(bag.pop(), Some(4));
assert_eq!(bag.pop(), Some(4));
assert!(bag.pop().is_none());

Trait Implementations

impl<T: Debug, const ARRAY_LEN: usize> Debug for Bag<T, ARRAY_LEN>

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

Formats the value using the given formatter.

impl<T> Default for Bag<T, DEFAULT_ARRAY_LEN>

fn default() -> Self

Returns the “default value” for a type.

impl<T, const ARRAY_LEN: usize> Drop for Bag<T, ARRAY_LEN>

fn drop(&mut self)

Executes the destructor for this type.