some, every, and includes

Answer yes/no questions about an array without building a new one.

some is true if at least one item passes. every is true only if all pass. includes checks whether a value is in the array (great for ids/roles). 

Results appear here.

Run a boolean check.

Important JavaScript

const scores = [88, 64, 91, 55];
const roles = ["guard", "forward", "guard"];

scores.some((n) => n >= 90);   // true — at least one
scores.every((n) => n >= 60);  // false — 55 fails

roles.includes("guard");       // true
roles.includes("center");      // false

// Tip: includes is for values already in the array.
// For objects, use some: players.some((p) => p.id === 3)