Iterate an array as a pair (current, next) in JavaScript

Question

In the question Iterate a list as pair (current, next) in Python, the OP is interested in iterating a Python list as a series of current, next pairs. I have th

Answer 1

Another solution using iterables and generator functions:

function * pairwise (iterable) {
    const iterator = iterable[Symbol.iterator]()
    let current = iterator.next()
    let next = iterator.next()
    while (!current.done) {
        yield [current.value, next.value]
        current = next
        next = iterator.next()
    }
}

console.log(...pairwise([]))
console.log(...pairwise(['apple']))
console.log(...pairwise(['apple', 'orange', 'kiwi', 'banana']))
console.log(...pairwise(new Set(['apple', 'orange', 'kiwi', 'banana'])))

Advantages:

• Works on all iterables, not only arrays (eg. Sets).
• Does not create any intermediate or temporary array.
• Lazy evaluated, works efficiently on very large iterables.