Factorial promise/generator test

factorialCallbackTest.js

function factorialCallback(acc, n, callback) {
  if (n === 0) {
    callback(acc);
  } else {
    setImmediate(() => factorialCallback(acc * n, n - 1, callback));
  }
}

function timedFactorialCallback(n) {
  const start = new Date();
  const result = factorialCallback(1, n, () => console.log(`factorialCallback finished in: ${new Date() - start}`));
  return result;
}

timedFactorialCallback(100000);

factorialGeneratorTest.js

function* Factorial() {
  var n = 1, total = 1;
  while (true) {
    total = total * n++;
    yield total;
  };
}

function factorialGenerators(n) {
  var f = Factorial(), k, nf;
  for (k = 0; k < n; k += 1) {
    nf = f.next().value;
  }
  return nf;
}

function timedFactorialGenerators(n) {
  const start = new Date();
  const result = factorialGenerators(n)
  console.log(`factorialGenerators finished in: ${new Date() - start}`);
  return result;
}

timedFactorialGenerators(100000);

factorialGeneratorTryCatchTest.js

function* FactorialTryCatch() {
  var n = 1, total = 1;
  while (true) {
    try {
      total = total * n++;
      yield total;
    } catch (e) {
      console.log(e);
    }
  };
}

function factorialGeneratorsTryCatch(n) {
  var f = FactorialTryCatch(), k, nf;
  for (k = 0; k < n; k += 1) {
    nf = f.next().value;
  }
  return nf;
}

function timedFactorialGeneratorsTryCatch(n) {
  const start = new Date();
  const result = factorialGeneratorsTryCatch(n)
  console.log(`factorialGeneratorsTryCatch finished in: ${new Date() - start}`);
  return result;
}

timedFactorialGeneratorsTryCatch(100000);

factorialPromisesTest.js

function factorialPromises(n) {
  var start = Promise.resolve(n);
  while (n -= 1) {
    start = start.then(function (n, value) {
      // console.log('n', n, 'value', value)
      return value * n;
    }.bind(null, n));
  }
  return start;
}

function timedFactorialPromise(n) {
  const start = new Date();
  const result = factorialPromises(n);
  result.then(() => console.log(`factorialPromises finished in: ${new Date() - start}`));
  return result;
}

timedFactorialPromise(100000);

results

johnhosx :: ~ » node factorialCallbackTest.js
factorialCallback finished in: 187
johnhosx :: ~ » node factorialGeneratorTryCatchTest.js
factorialGeneratorsTryCatch finished in: 46
johnhosx :: ~ » node factorialGeneratorTest.js
factorialGenerators finished in: 44
johnhosx :: ~ » node factorialPromisesTest.js
factorialPromises finished in: 406
johnhosx :: ~ » node -v
v6.6.0
johnhosx :: ~ » nvm use 6.5
Now using node v6.5.0 (npm v3.10.3)
johnhosx :: ~ » node factorialCallbackTest.js
factorialCallback finished in: 171
johnhosx :: ~ » node factorialGeneratorTryCatchTest.js
factorialGeneratorsTryCatch finished in: 53
johnhosx :: ~ » node factorialGeneratorTest.js
factorialGenerators finished in: 52
johnhosx :: ~ » node factorialPromisesTest.js
factorialPromises finished in: 416
johnhosx :: ~ » node -v
v6.5.0
johnhosx :: ~ »

good work