# JavaScript (ES6), 42 bytes, [Cracked](https://codegolf.stackexchange.com/a/135705) <!-- language-all: lang-javascript --> x=>{while(!(Array.isArray(x)&&x==",,,"));} >! An empty array of length 4 (`new Array(4)`), when coerced into a string with `==`, becomes `,,,`. [Try it online!][TIO-j5js6aw8] [TIO-j5js6aw8]: https://tio.run/##y0osSyxOLsosKNHNy09J/Z9m@7/C1q66PCMzJ1VDUcOxqCixUi@zGExrVGiqqVXY2irp6OgoaWpa1/5Pzs8rzs9J1cvJT9dI04CK/wcA "JavaScript (Node.js) – Try It Online"