Erase pointers of their concrete type and store type-erased pointers.

This is roughly equivalent to C's void*, but it does not use libc::c_void.

There are two main useful reasons to type erase pointers in Rust:

• Removing viral generics from internal implementation details. If the internals truly don't care about the stored type, treating it opaquely reduces monomorphization cost both to the author and the compiler.
• Thin pointers to ?Sized types. If an unsized type stores its metadata inline, then it can implement Erasable and be used behind type-erased pointers. The type erased pointer does not have to carry the metadata, and the fat pointer can be recovered from the inline metadata. We provide the Thin wrapper type to provide thin pointer types.

Related Crates

• ptr-union: Pointer unions the size of a pointer.
• rc-borrow: Borrowed forms of Rc and Arc.
• rc-box: Known unique forms of Rc and Arc.
• slice-dst: Support for custom slice-based DSTs.

Minimum Supported Rust Version

We require a minimum Rust version of 1.41.0. This is for an adjustment of local trait impl checking.

Minimum version support is only guaranteed with minimal version resolution (-Z minimal-versions/--minimal-versions) due to how dependencies are handled. The minimum version of Rust will only be incremented with minor version bumps, not patch version bumps, and will be deliberate and clearly noted in change notes.

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE/APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE/MIT or http://opensource.org/licenses/MIT)

at your option.

If you are a highly paid worker at any company that prioritises profit over people, you can still use this crate. I simply wish you will unionise and push back against the obsession for growth, control, and power that is rampant in your workplace. Please take a stand against the horrible working conditions they inflict on your lesser paid colleagues, and more generally their disrespect for the very human rights they claim to fight for.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.