Cycle generator

JavaScript, Function, Generator · Oct 11, 2020

Creates a generator, looping over the given array indefinitely.

Use a non-terminating while loop, that will yield a value every time Generator.prototype.next() is called.
Use the module operator (%) with Array.prototype.length to get the next value's index and increment the counter after each yield statement.

const cycleGenerator = function* (arr) {
  let i = 0;
  while (true) {
    yield arr[i % arr.length];
    i++;
  }
};

const binaryCycle = cycleGenerator([0, 1]);
binaryCycle.next(); // { value: 0, done: false }
binaryCycle.next(); // { value: 1, done: false }
binaryCycle.next(); // { value: 0, done: false }
binaryCycle.next(); // { value: 1, done: false }

Written by Angelos Chalaris

I'm Angelos Chalaris, a JavaScript software engineer, based in Athens, Greece. The best snippets from my coding adventures are published here to help others learn to code.

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