Sprawdź, czy tablica w warunkach JavaScript

const x = thisIsPossiblyAnArray?.[0];
if (x) {
 console.log("the value of index 0 is", x);
} else {
 console.log("x is undefined as thisIsPossiblyAnArray is either not an Array or is an Array with no item at index 0")
}
Anxious Alligator