// Array → Array.prototype → Object.prototype → null
// Function → Function.prototype → Object.prototype → null
// String → String.prototype → Object.prototype → null

const arr = [1, 2, 3];

// These methods are defined on Array.prototype:
// push, pop, map, filter, reduce, find, sort, forEach, etc.

console.log(arr.__proto__ === Array.prototype); // true
console.log(Array.prototype.__proto__ === Object.prototype); // true

function greet() {}
// call, apply, bind, etc. are on Function.prototype

console.log(greet.__proto__ === Function.prototype); // true
console.log(Function.prototype.__proto__ === Object.prototype); // true

// Methods all objects inherit:
// toString, hasOwnProperty, valueOf, isPrototypeOf, propertyIsEnumerable

const obj = {};
console.log(obj.__proto__ === Object.prototype); // true
console.log(Object.prototype.__proto__); // null — end of chain

const arr = [3, 1, 2];

// arr inherits from Array.prototype
arr.sort(); // Array.prototype.sort
console.log(arr); // [1, 2, 3]

// arr also inherits from Object.prototype (via Array.prototype)
console.log(arr.hasOwnProperty(0)); // Object.prototype.hasOwnProperty

// ❌ Bad practice — don't modify built-in prototypes
Array.prototype.first = function() { return this[0]; };
// Now ALL arrays have this method — potential conflicts!

// ❌ Even worse — overwriting existing methods
Array.prototype.push = function() {
  console.log('push disabled');
  // Breaks all arrays!
};

const arr = [1, 2, 3];

// Check if it's an own property
console.log(arr.hasOwnProperty('map'));  // false — inherited

// Check the prototype
console.log('map' in arr);                // true — found in chain
console.log(arr.map === Array.prototype.map); // true — same reference