| # yoke [](https://crates.io/crates/yoke) |
| |
| <!-- cargo-rdme start --> |
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| This crate provides [`Yoke<Y, C>`][Yoke], which allows one to "yoke" (attach) a zero-copy deserialized |
| object (say, a [`Cow<'a, str>`](alloc::borrow::Cow)) to the source it was deserialized from, (say, an [`Rc<[u8]>`](alloc::rc::Rc)), |
| known in this crate as a "cart", producing a type that looks like `Yoke<Cow<'static, str>, Rc<[u8]>>` |
| and can be moved around with impunity. |
| |
| Succinctly, this allows one to "erase" static lifetimes and turn them into dynamic ones, similarly |
| to how `dyn` allows one to "erase" static types and turn them into dynamic ones. |
| |
| Most of the time the yokeable `Y` type will be some kind of zero-copy deserializable |
| abstraction, potentially with an owned variant (like [`Cow`](alloc::borrow::Cow), |
| [`ZeroVec`](https://docs.rs/zerovec), or an aggregate containing such types), and the cart `C` will be some smart pointer like |
| [`Box<T>`](alloc::boxed::Box), [`Rc<T>`](alloc::rc::Rc), or [`Arc<T>`](std::sync::Arc), potentially wrapped in an [`Option<T>`](Option). |
| |
| The key behind this crate is [`Yoke::get()`], where calling [`.get()`][Yoke::get] on a type like |
| `Yoke<Cow<'static, str>, _>` will get you a short-lived `&'a Cow<'a, str>`, restricted to the |
| lifetime of the borrow used during [`.get()`](Yoke::get). This is entirely safe since the `Cow` borrows from |
| the cart type `C`, which cannot be interfered with as long as the `Yoke` is borrowed by [`.get()`](Yoke::get). |
| [`.get()`](Yoke::get) protects access by essentially reifying the erased lifetime to a safe local one |
| when necessary. |
| |
| See the documentation of [`Yoke`] for more details. |
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| <!-- cargo-rdme end --> |
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| ## More Information |
| |
| For more information on development, authorship, contributing etc. please visit [`ICU4X home page`](https://github.com/unicode-org/icu4x). |
