fuction_test_20150915.js

function fuck1 () {
  function readdir (dir) {
    return ['a', 'b', 'c', 'd', 'e'].map(function (n) {
      return dir + n;
    }).filter(function (n) {
      return n;
    });
  }
  function addTo (obj, list) {
    list.forEach(function (n) {
      obj[n] = true;
    });
  }
  var ret = {};
  addTo(ret, readdir('a'));
  addTo(ret, readdir('b'));
  return ret;
}

function readdir (dir) {
  return ['a', 'b', 'c', 'd', 'e'].map(function (n) {
    return dir + n;
  }).filter(function (n) {
    return n;
  });
}
function addTo (obj, list) {
  list.forEach(function (n) {
    obj[n] = true;
  });
}
function fuck2 () {
  var ret = {};
  addTo(ret, readdir('a'));
  addTo(ret, readdir('b'));
  return ret;
}


function MB (n) {
  return (n / 1024 / 1024).toFixed(1);
}
function test (title, times, fn) {
  var start = Date.now();
  var heapStart = process.memoryUsage().heapUsed;
  for (var i = 0; i < times; i++) {
    fn();
  }
  var end = Date.now();
  var heapEnd = process.memoryUsage().heapUsed;
  console.log('%s, %s times, spent %sms, heapUsed %sMB to %sMB', title, times, end - start, MB(heapStart), MB(heapEnd));
}


test('fuck1', 1000000, fuck1);
test('fuck2', 1000000, fuck2);