docs/bevy/examples/no_std/README.md 1.4 K · 18 lines · raw · history

1 # `no_std` Examples
2
3 This folder contains examples for how to work with `no_std` targets and Bevy.
4 Refer to each example individually for details around how it works and what features you may need to enable/disable to allow a particular target to work.
5
6 ## What is `no_std`?
7
8 `no_std` is a Rust term for software which doesn't rely on the standard library, [`std`](https://doc.rust-lang.org/stable/std/).
9 The typical use for `no_std` is in embedded software, where the device simply doesn't support the standard library.
10 For example, a [Raspberry Pi Pico](https://www.raspberrypi.com/documentation/microcontrollers/pico-series.html) has no operating system to support threads or filesystem operations.
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12 For these platforms, Rust has a more fundamental alternative to `std`, [`core`](https://doc.rust-lang.org/stable/core/).
13 A large portion of Rust's `std` actually just re-exports items from `core`, such as iterators, `Result`, and `Option`.
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15 In addition, `std` also re-exports from another crate, [`alloc`](https://doc.rust-lang.org/stable/alloc/).
16 This crate is similar to `core` in that it's generally available on all platforms.
17 Where it differs is that its inclusion requires access to a [global allocator](https://doc.rust-lang.org/stable/std/alloc/trait.GlobalAlloc.html).
18 Currently, Bevy relies heavily on allocation, so we consider `alloc` to be just as available, since without it, Bevy will not compile.