Bug: 170637881

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  1. 7cbbfbf Make weak-table available to product and vendor am: 1a1b0c2fea am: 9b7997db35 by Matthew Maurer · 7 months ago build-tools-release main master
  2. 9b7997d Make weak-table available to product and vendor am: 1a1b0c2fea by Matthew Maurer · 7 months ago android-u-beta-1-gpl
  3. 1a1b0c2 Make weak-table available to product and vendor by Matthew Maurer · 7 months ago
  4. 98e4076 Update weak-table to 0.3.2 am: 77e4bb9dcd am: 0a3ad2af3d am: 3f9b4dcddd by David LeGare · 1 year, 7 months ago android13-d2-release android13-d3-s1-release android13-d4-release android13-d4-s1-release android13-d4-s2-release android13-dev android13-frc-odp-release android13-mainline-go-adservices-release android13-qpr1-release android13-qpr1-s1-release android13-qpr1-s2-release android13-qpr1-s3-release android13-qpr1-s4-release android13-qpr1-s5-release android13-qpr1-s6-release android13-qpr1-s7-release android13-qpr1-s8-release android13-qpr2-b-s1-release android13-qpr2-release android13-qpr2-s1-release android13-qpr2-s10-release android13-qpr2-s11-release android13-qpr2-s12-release android13-qpr2-s2-release android13-qpr2-s3-release android13-qpr2-s5-release android13-qpr2-s6-release android13-qpr2-s7-release android13-qpr2-s8-release android13-qpr2-s9-release android13-qpr3-c-s1-release android13-qpr3-c-s10-release android13-qpr3-c-s11-release android13-qpr3-c-s12-release android13-qpr3-c-s2-release android13-qpr3-c-s3-release android13-qpr3-c-s4-release android13-qpr3-c-s5-release android13-qpr3-c-s6-release android13-qpr3-c-s7-release android13-qpr3-c-s8-release android13-qpr3-release android13-qpr3-s1-release android13-qpr3-s10-release android13-qpr3-s11-release android13-qpr3-s12-release android13-qpr3-s13-release android13-qpr3-s2-release android13-qpr3-s3-release android13-qpr3-s4-release android13-qpr3-s5-release android13-qpr3-s6-release android13-qpr3-s7-release android13-qpr3-s8-release android13-qpr3-s9-release main-16k main-16k-with-phones aml_go_ads_330913000 aml_go_ads_330915000 aml_go_ads_330915100 aml_go_odp_330912000 android-13.0.0_r16 android-13.0.0_r17 android-13.0.0_r18 android-13.0.0_r19 android-13.0.0_r20 android-13.0.0_r21 android-13.0.0_r22 android-13.0.0_r23 android-13.0.0_r24 android-13.0.0_r27 android-13.0.0_r28 android-13.0.0_r29 android-13.0.0_r30 android-13.0.0_r32 android-13.0.0_r33 android-13.0.0_r34 android-13.0.0_r35 android-13.0.0_r36 android-13.0.0_r37 android-13.0.0_r38 android-13.0.0_r39 android-13.0.0_r40 android-13.0.0_r41 android-13.0.0_r42 android-13.0.0_r43 android-13.0.0_r44 android-13.0.0_r45 android-13.0.0_r46 android-13.0.0_r47 android-13.0.0_r48 android-13.0.0_r49 android-13.0.0_r50 android-13.0.0_r51 android-13.0.0_r52 android-13.0.0_r53 android-13.0.0_r54 android-13.0.0_r55 android-13.0.0_r56 android-13.0.0_r57 android-13.0.0_r58 android-13.0.0_r59 android-13.0.0_r60 android-13.0.0_r61 android-13.0.0_r62 android-13.0.0_r63 android-13.0.0_r64 android-13.0.0_r65 android-13.0.0_r66 android-13.0.0_r67 android-13.0.0_r68 android-13.0.0_r69 android-13.0.0_r70 android-13.0.0_r71 android-13.0.0_r72 android-13.0.0_r73 android-13.0.0_r74 android-13.0.0_r75 android-13.0.0_r76 android-13.0.0_r77 android-13.0.0_r78 android-13.0.0_r79 android-13.0.0_r80 android-13.0.0_r81 android-13.0.0_r82 t_frc_ase_330444010 t_frc_odp_330442000 t_frc_odp_330442040
  5. 3f9b4dc Update weak-table to 0.3.2 am: 77e4bb9dcd am: 0a3ad2af3d by David LeGare · 1 year, 7 months ago

weak-table: weak hash maps and sets for Rust

Build Status Crates.io License: MIT

This crate defines several kinds of weak hash maps and sets. See the full API documentation for details.

Rust version support

This crate supports Rust version 1.46 and later.

Crate features

weak-table is built with the std feature, which enables functionality dependent on the std library, enabled by default. Optionally, the following dependency may be enabled:

  • ahash: use ahash’s hasher rather than the std hasher

If the std feature is disabled (for no_std) then the ahash dependency must be enabled.


Here we create a weak hash map and demonstrate that it forgets mappings whose keys expire:

use weak_table::WeakKeyHashMap;
use std::sync::{Arc, Weak};

let mut table = <WeakKeyHashMap<Weak<str>, u32>>::new();
let one = Arc::<str>::from("one");
let two = Arc::<str>::from("two");

table.insert(one.clone(), 1);

assert_eq!( table.get("one"), Some(&1) );
assert_eq!( table.get("two"), None );

table.insert(two.clone(), 2);
*table.get_mut(&one).unwrap() += 10;

assert_eq!( table.get("one"), Some(&11) );
assert_eq!( table.get("two"), Some(&2) );


assert_eq!( table.get("one"), None );
assert_eq!( table.get("two"), Some(&2) );

Here we use a weak hash set to implement a simple string interning facility:

use weak_table::WeakHashSet;
use std::ops::Deref;
use std::rc::{Rc, Weak};

#[derive(Clone, Debug)]
pub struct Symbol(Rc<str>);

impl PartialEq for Symbol {
    fn eq(&self, other: &Symbol) -> bool {
        Rc::ptr_eq(&self.0, &other.0)

impl Eq for Symbol {}

impl Deref for Symbol {
    type Target = str;
    fn deref(&self) -> &str {

#[derive(Debug, Default)]
pub struct SymbolTable(WeakHashSet<Weak<str>>);

impl SymbolTable {
    pub fn new() -> Self {

    pub fn intern(&mut self, name: &str) -> Symbol {
        if let Some(rc) = self.0.get(name) {
        } else {
            let rc = Rc::<str>::from(name);

fn interning() {
    let mut tab = SymbolTable::new();

    let a0 = tab.intern("a");
    let a1 = tab.intern("a");
    let b  = tab.intern("b");

    assert_eq!(a0, a1);
    assert_ne!(a0, b);