See this [javascript-adding-booleans](https://stackoverflow.com/questions/20555321/javascript-adding-booleans)
– flyingfoxOct 16 '22 at 11:08
`[]` is an empty array, which is a truthy value. `!` negates a value. So we have `false + true + true`. The `+` operator converts its operands, to numbers if possible or to strings if not. `false` converts to `0`, `true` converts to `1`. Thus: 2.
– T.J. CrowderOct 16 '22 at 11:13