rs-intrusive - Support macros for building intrusive data structures

in Rust.

An intrusive structure is a general-purpose structure directly embedded within a containing structure, in order to add that general-purpose facility to the container. As an example, one might use an intrusive "link" structure to allow objects to be organized in a linked-list:

```rust struct Link { next: Option, } struct List { head: Option, tail: Option, }

struct Container { link: Link, } ```

While this module does not provide a linked-list implementation (for separation-of-concerns reasons, I believe a linked-list implementation belongs in a separate crate), it does provide some necessary abstractions for using intrusive structures:

• The field_offset! macro, which identifies the location of a field in a containing structure. This isn't too useful in itself, but is necessary to support:
• The intrusive! macro, which provides a newtype for using "intrusive" fields to work with the container object.

Usage

```rust

[macro_use(intrusive)]

extern crate "intrusive";

struct Link { next: Option, } // FIXME: is this legal? want to enforce constraint that List only // operates against intrusive Links. struct List where T: Intrusive, T::Field: Link, { head: Option, }

struct Container { link: Link, } intrusive!(ContainerLink = Container:link::Link);

fn create() -> List { let x = Box::new(Container { link: None }); let link: ContainerLink = intrusive::Intrusive::movefrom(x); List { head: Some(link) } } fn head(list: List) -> Box { list.head.unwrap().containerof() } ```

Contributing

1. Fork it ( https://github.com/aidancully/rs-intrusive/fork )
2. Create your feature branch (git checkout -b my-new-feature)
3. Commit your changes (git commit -am 'Add some feature')
4. Push to the branch (git push origin my-new-feature)
5. Create a new Pull Request