Repeat generator

JavaScript, Function, Generator · Oct 11, 2020

Creates a generator, repeating the given value indefinitely.

Use a non-terminating while loop, that will yield a value every time Generator.prototype.next() is called.
Use the return value of the yield statement to update the returned value if the passed value is not undefined.

const repeatGenerator = function* (val) {
  let v = val;
  while (true) {
    let newV = yield v;
    if (newV !== undefined) v = newV;
  }
};

const repeater = repeatGenerator(5);
repeater.next(); // { value: 5, done: false }
repeater.next(); // { value: 5, done: false }
repeater.next(4); // { value: 4, done: false }
repeater.next(); // { value: 4, 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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