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yog_data/model/atom/
local.rs

1//! The table a process keeps itself: the runtime's, or a tool's.
2use super::{HashMap, OnceLock, RwLock};
3
4#[derive(Default)]
5struct Names {
6    numbers: HashMap<&'static str, u32>,
7    names: Vec<&'static str>,
8}
9
10static NAMES: OnceLock<RwLock<Names>> = OnceLock::new();
11
12fn names() -> &'static RwLock<Names> {
13    NAMES.get_or_init(Default::default)
14}
15
16/// `name`'s number, made the first time (its text kept for good).
17pub fn intern(name: &str) -> u32 {
18    if let Some(&n) = names().read().numbers.get(name) {
19        return n;
20    }
21    let mut t = names().write();
22    if let Some(&n) = t.numbers.get(name) {
23        return n;
24    }
25    let kept: &'static str = Box::leak(name.into());
26    let n = u32::try_from(t.names.len()).unwrap_or(u32::MAX);
27    t.names.push(kept);
28    t.numbers.insert(kept, n);
29    n
30}
31
32pub fn name(n: u32) -> Option<&'static str> {
33    names().read().names.get(n as usize).copied()
34}