qindex_multi

API Documentation

This crate provides MultiIndexable, through which its implementors allow us to violate basic borrowing-rules when indexing them (using Index[Mut]) , as long as we adhere to them for each individual element.

In other words: We can index a collection mutably and immutable multiple times at once, as long as there are no read/write clashes.

NOTE: MultiIndexable is currently not implemented for libstd's HashMap and BTreeMap, due to them missing IndexMut-implementations. This will change when IndexAssign-functionality lands.

This crate requires the latest rust nightly to compile.

TODO

• Doc, Tests, Examples

Example Usage

```rust

![feature(slice_patterns)]

extern crate qcollect; extern crate qindexmulti; extern crate vecmap;

use vecmap::VecMap; use qindexmulti::{MultiIndexable, MultiIndex};

[test]

fn test1(){ let mut data = VecMap::new(); data.insert(0, 100u16); data.insert(2, 200); data.insert(20, 300); data.insert(200, 400);

let read_indicies = vec![0, 2, 20];
let write_indicies = vec![200];

let multi_idx = MultiIndex::new(read_indicies, write_indicies);

{
    let mut output = data.index_multi(&multi_idx);

    let [a, b, c]: [_; 3] = qcollect::iter_into_fixed(output.read);
    let d = output.write.next().unwrap();
    *d += *a + *b + c; 

}
assert_eq!(data[200], 1000);

} ```