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diff --git a/vendor/once_cell/README.md b/vendor/once_cell/README.md deleted file mode 100644 index 2ac9b53..0000000 --- a/vendor/once_cell/README.md +++ /dev/null @@ -1,57 +0,0 @@ -<p align="center"><img src="design/logo.png" alt="once_cell"></p> - - -[![Build Status](https://github.com/matklad/once_cell/actions/workflows/ci.yaml/badge.svg)](https://github.com/matklad/once_cell/actions) -[![Crates.io](https://img.shields.io/crates/v/once_cell.svg)](https://crates.io/crates/once_cell) -[![API reference](https://docs.rs/once_cell/badge.svg)](https://docs.rs/once_cell/) - -# Overview - -`once_cell` provides two new cell-like types, `unsync::OnceCell` and `sync::OnceCell`. `OnceCell` -might store arbitrary non-`Copy` types, can be assigned to at most once and provide direct access -to the stored contents. In a nutshell, API looks *roughly* like this: - -```rust -impl OnceCell<T> { - fn new() -> OnceCell<T> { ... } - fn set(&self, value: T) -> Result<(), T> { ... } - fn get(&self) -> Option<&T> { ... } -} -``` - -Note that, like with `RefCell` and `Mutex`, the `set` method requires only a shared reference. -Because of the single assignment restriction `get` can return an `&T` instead of `Ref<T>` -or `MutexGuard<T>`. - -`once_cell` also has a `Lazy<T>` type, build on top of `OnceCell` which provides the same API as -the `lazy_static!` macro, but without using any macros: - -```rust -use std::{sync::Mutex, collections::HashMap}; -use once_cell::sync::Lazy; - -static GLOBAL_DATA: Lazy<Mutex<HashMap<i32, String>>> = Lazy::new(|| { - let mut m = HashMap::new(); - m.insert(13, "Spica".to_string()); - m.insert(74, "Hoyten".to_string()); - Mutex::new(m) -}); - -fn main() { - println!("{:?}", GLOBAL_DATA.lock().unwrap()); -} -``` - -More patterns and use-cases are in the [docs](https://docs.rs/once_cell/)! - -# Related crates - -* [double-checked-cell](https://github.com/niklasf/double-checked-cell) -* [lazy-init](https://crates.io/crates/lazy-init) -* [lazycell](https://crates.io/crates/lazycell) -* [mitochondria](https://crates.io/crates/mitochondria) -* [lazy_static](https://crates.io/crates/lazy_static) -* [async_once_cell](https://crates.io/crates/async_once_cell) -* [generic_once_cell](https://crates.io/crates/generic_once_cell) (bring your own mutex) - -Parts of `once_cell` API are included into `std` [as of Rust 1.70.0](https://github.com/rust-lang/rust/pull/105587). |