Module substudy::contexts

Iteration in context, with the previous and next value, if available.

use substudy::contexts::{Context, ItemsInContextExt};

let v: &[u8] = &[1, 2];
let ctxs: Vec<Context<u8>> = v.items_in_context()
    .map(|ctx| ctx.cloned())
    .collect();

assert_eq!(v.len(), ctxs.len());

assert_eq!(None,    ctxs[0].prev);
assert_eq!(1,       ctxs[0].curr);
assert_eq!(Some(2), ctxs[0].next);

assert_eq!(Some(1), ctxs[1].prev);
assert_eq!(2,       ctxs[1].curr);
assert_eq!(None,    ctxs[1].next);

This file would be pretty high-order magic in Haskell, where we wouldn't need to worry about the difference between values and references. In Rust, it's a bit like an evil hybrid of the abstraction of Haskell and the reference wonkiness of C++. It works well enough in practice, but I'm not sure how I feel about it.

Structs

Context	An item in a slice, possibly with the item before or after it.
ItemsInContext	Iterator type for ItemsInContextExt.
OptContext	Like Context, but curr is also optional.

Traits

ItemsInContextExt

Provides the items_in_context method.