Vince McMahon Discovers JavaScript Weirdness

let l = [1,2,3,4] undefined 0 in l true "0" in l true 4 in l false

A four-panel reaction meme shows Vince McMahon becoming increasingly shocked while testing JavaScript’s `in` operator on an array. The joke is that `0 in l` and `"0" in l` return true because they refer to the array index, while `4 in l` returns false because the last index is 3. It is used to react to surprising programming behavior or confusing technical quirks.

• @gentoomemes / 6547 2023-09-29