Collection of functional utilities for Rust.
```rust let xs = vec![1, 2, 3]; let ys = vec![4, 5, 6];
asserteq!(vector::zipwith(xs, ys, |x, y| x + y), vec![5, 7, 9]); ```
```rust let xs = vec![1, 3, 5, 7, 9]; let is_odd = |x| x % 2 != 0;
asserteq!(truth::all(&xs, isodd), true) ```