const numbers = [1, 2, 3, 4, 5, 6];

const result = numbers
  .map(x => x * 2)
  .filter(x => x > 6)
  .reduce((acc, x) => {
    console.log(`Processing ${x}, acc: ${acc}`);
    return acc + x;
  }, 0);

console.log(`Final result: ${result}`);

const obj = {
  value: 42,
  [Symbol.toPrimitive](hint) {
    if (hint === 'number') return this.value * 2;
    if (hint === 'string') return `Value: ${this.value}`;
    return this.value + 10;
  }
};

console.log(+obj);
console.log(`${obj}`);
console.log(obj + 5);
console.log(Number(obj));

function mysteryFunction() {
  console.log(x);
  console.log(y);
  console.log(z);
  
  var x = 'declared';
  let y = 'block-scoped';
  const z = 'constant';
  
  console.log(x);
  console.log(y);
  console.log(z);
}

mysteryFunction();

function Vehicle(type) {
  this.type = type;
  this.wheels = 4;
}

Vehicle.prototype.getInfo = function() {
  return `${this.type} with ${this.wheels} wheels`;
};

const car = new Vehicle('sedan');
const bike = Vehicle('motorcycle');

console.log(car.getInfo());
console.log(typeof bike);
console.log(bike?.type || 'undefined');

function* innerGenerator() {
  yield 1;
  yield 2;
  return 'inner-done';
}

function* outerGenerator() {
  yield 'start';
  const result = yield* innerGenerator();
  yield result;
  yield 'end';
}

const gen = outerGenerator();
console.log(gen.next().value);
console.log(gen.next().value);
console.log(gen.next().value);
console.log(gen.next().value);
console.log(gen.next().value);

function processData() {
  const results = [];
  
  for (let i = 0; i < 3; i++) {
    const multiplier = i + 1;
    
    setTimeout(() => {
      results.push(i * multiplier);
    }, 0);
  }
  
  setTimeout(() => {
    console.log(results.join(','));
  }, 10);
}

processData();

class Calculator {
  constructor(value) {
    this.value = value;
  }
  
  add(num) {
    this.value += num;
    return this;
  }
  
  multiply(num) {
    this.value *= num;
    return this;
  }
}

const calc = new Calculator(5);
const addMethod = calc.add;
const result = addMethod.call(calc, 3).multiply(2);
console.log(result.value);