bevy/crates/bevy_ptr/README.md

# Bevy Ptr

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The `bevy_ptr` crate provides low-level abstractions for working with pointers in a more safe way than using rust's raw pointers.

Rust has lifetimed and typed references (`&'a T`), unlifetimed and typed references (`*const T`), but no lifetimed but untyped references.
`bevy_ptr` adds them, called `Ptr<'a>`, `PtrMut<'a>` and `OwningPtr<'a>`.
These types are lifetime-checked so can never lead to problems like use-after-frees and must always point to valid data.
add and fix shields in Readmes (#9993) # Objective Fix shields ## Solution - Correct shield in the Bevy ECS Readme, where only the MIT license is displayed ![Screenshot 2023-10-01 at 18 28 27](https://github.com/bevyengine/bevy/assets/104745335/a736a65e-0d47-4d9e-b32d-0b843a00922c) - Add shields to other Readmes. - homogenize shields and titles. 2023-10-15 00:52:31 +00:00			`# Bevy Ptr`

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`bevy_ptr` standalone crate (#4653) # Objective The pointer types introduced in #3001 are useful not just in `bevy_ecs`, but also in crates like `bevy_reflect` (#4475) or even outside of bevy. ## Solution Extract `Ptr<'a>`, `PtrMut<'a>`, `OwnedPtr<'a>`, `ThinSlicePtr<'a, T>` and `UnsafeCellDeref` from `bevy_ecs::ptr` into `bevy_ptr`. Note: `bevy_ecs` still reexports the `bevy_ptr` as `bevy_ecs::ptr` so that crates like `bevy_transform` can use the `Bundle` derive without needing to depend on `bevy_ptr` themselves. 2022-05-04 19:16:10 +00:00
			The `bevy_ptr` crate provides low-level abstractions for working with pointers in a more safe way than using rust's raw pointers.

			Rust has lifetimed and typed references (`&'a T`), unlifetimed and typed references (`*const T`), but no lifetimed but untyped references.
			`bevy_ptr` adds them, called `Ptr<'a>`, `PtrMut<'a>` and `OwningPtr<'a>`.
			`These types are lifetime-checked so can never lead to problems like use-after-frees and must always point to valid data.`