Rust’s slice::windows is really cool

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This post is one of several that outline my perspective on learning Rust as someone who primarily uses JavaScript. You can find the rest here.

Rust has a lot of powerful features associated with its primitives and standard library. A cool one I just came across is the method slice::windows. This method returns an iterator over a slice. The iterator length can be specified. It lets you iterate over a slice and have a window of a specific size on each pass. For example:

// windows.rs
let slice = ['w', 'i', 'n', 'd', 'o', 'w', 's'];
for window in slice.windows(2) {
  &println!{"[{}, {}]", window[0], window[1]};
}
// prints: [w, i] -> [i, n] -> [n, d] -> [d, o] -> [o, w] -> [w, s]

This is pretty cool, and doesn’t really have a parallel in JavaScript. The closest that I can come up with to achieve the same is this:

// windows.js
let slice = ["w", "i", "n", "d", "o", "w", "s"];
slice.forEach((char, index) => {
  if (index === slice.length - 1) return;
  console.log(`[${slice[index]}, ${slice[index + 1]}]`);
});

The JavaScript approach is definitely less ergonomic, and I really like the concept of windows as an abstraction for use with iterators.

Thanks for reading.