# fat_type
`fat_type` provides the type `Fat<T, U>`, which combines a value of type `U` with the metadata
needed to construct references to it as a `T`.
Because the metadata is stored with the value instead of in references, `Fat<T>` is [`Thin`]. This
property is mainly useful in niche foreign-function-interface use-cases or in memory-constrained
environments. As such, this library is [`no_std`].
In particular, the author has found this crate useful in passing around Rust closure types as
*userdata* pointers in several C-language FFI projects.
# Documentation
Inline rustdoc documentation is available. A mirror of this documentation is available at
<https://docs.rs/fat_type>.
# Contributing
`fat_type` is developed at [GitLab].
This crate is rigorously tested with [Miri] and maintains full compliance with [strict pointer
provenance].
Reasonable performance, correctness, documentation, and ease-of-use contributions are always
welcome. [Bug reports][Issues] are accepted through GitLab, but feature requests are not.
## Pull Requests
Please ensure pull requests match the existing coding style and are formatted with [rustfmt].
Spelling and grammatical errors are considered bugs, so please use spell-checking facilities prior
to submitting a contribution.
## Contribution Agreement
By contributing, you grant all contributors a perpetual, worldwide, non-exclusive, no-charge,
royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly
display, publicly perform, relicense, sublicense, and distribute your contributions.
Additionally, you affirm that you are legally entitled to grant such license and that your
contributions are not and will not become patent-encumbered. In the event that you discover that
such affirmation was made in error, you agree to post notice of such error in a conspicuous place
(such as a [GitLab Issue][Issues]) within three days.
# License
`fat_type` is licensed under the terms of the [Apache License, Version 2.0][Apache2] or the
[MIT License][MIT].
# Copyright
This document is Copyright (C) 2022 Nathan Sharp.
Permission is granted to reproduce this document, in any form, free of charge.
[Apache2]: https://www.apache.org/licenses/LICENSE-2.0
[GitLab]: https://gitlab.com/nwsharp/fat_type
[Issues]: https://gitlab.com/nwsharp/fat_type/-/issues
[MIT]: https://opensource.org/licenses/MIT
[Miri]: https://github.com/rust-lang/miri
[strict pointer provenance]: https://doc.rust-lang.org/nightly/std/ptr/index.html#strict-provenance
[`no_std`]: https://docs.rust-embedded.org/book/intro/no-std.html
[rustfmt]: https://github.com/rust-lang/rustfmt/blob/master/README.md#quick-start
[`Thin`]: https://doc.rust-lang.org/core/ptr/traitalias.Thin.html