ES6: Buffer Iterator

buffer_iterator.js

function BufferIterator(collection, bufferSize) {
  this[Symbol.iterator] = function () {
    let nextIndex = 0;

    return {
      next: () => {
        if (nextIndex < collection.length) {
          const buffer = new Array(bufferSize);
          for (let i = 0; i < bufferSize; i++) {
            buffer[i] = collection[nextIndex++];
          }
          return { value: buffer, done: false };
        }
        return { done: true };
      },
    };
  };
}

// Main
const arr = [1, 2, 3, 4, 5, 6];

for(let buff of new BufferIterator(arr, 2)) {
  console.log(buff);
}
//-> [1, 2] [3, 4] [5, 6]

for(let buff of new BufferIterator(arr, 3)) {
  console.log(buff);
}
//-> [1, 2, 3] [4, 5, 6]