number.js

Number.EPSILON
Number.isInteger(Infinity); // false
Number.isNaN("NaN"); // false

Math.acosh(3); // 1.762747174039086
Math.hypot(3, 4); // 5
Math.imul(Math.pow(2, 32) - 1, Math.pow(2, 32) - 2) // 2
;
"abcde".includes("cd"); // true
"abc".repeat(3); // "abcabcabc"

Array.from(document.querySelectorAll('*')); // Returns a real Array
Array.of(1, 2, 3) // Similar to new Array(...), but without special one-arg behavior
    [0, 0, 0].fill(7, 1) // [0,7,7]
    [1, 2, 3].find(x => x == 3) // 3
    [1, 2, 3].findIndex(x => x == 2) // 1
    [1, 2, 3, 4, 5].copyWithin(3, 0) // [1, 2, 3, 1, 2]
    ["a", "b", "c"].entries() // iterator [0, "a"], [1,"b"], [2,"c"]
    ["a", "b", "c"].keys() // iterator 0, 1, 2
    ["a", "b", "c"].values(); // iterator "a", "b", "c"

Object.assign(Point, { origin: new Point(0,0) });