Add cycleGenerator

snippets/cycleGenerator.md

@@ -0,0 +1,27 @@
+---
+title: cycleGenerator
+tags: function,generator,advanced
+---
+
+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.
+
+```js
+const cycleGenerator = function* (arr) {
+  let i = 0;
+  while (true) {
+    yield arr[i % arr.length];
+    i++;
+  }
+};
+```
+
+```js
+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 }
+```