28 lines
773 B
Markdown
28 lines
773 B
Markdown
---
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title: cycleGenerator
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tags: function,generator,advanced
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---
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Creates a generator, looping over the given array indefinitely.
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- Use a non-terminating `while` loop, that will `yield` a value every time `Generator.prototype.next()` is called.
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- Use the module operator (`%`) with `Array.prototype.length` to get the next value's index and increment the counter after each `yield` statement.
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```js
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const cycleGenerator = function* (arr) {
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let i = 0;
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while (true) {
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yield arr[i % arr.length];
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i++;
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}
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};
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```
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```js
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const binaryCycle = cycleGenerator([0, 1]);
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binaryCycle.next(); // { value: 0, done: false }
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binaryCycle.next(); // { value: 1, done: false }
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binaryCycle.next(); // { value: 0, done: false }
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binaryCycle.next(); // { value: 1, done: false }
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```
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