kepta

const arrayAddFirst = (a, b) => [a, ...b];

kepta

In this article I will take a very simplistic approach in understanding memory leaks and I will also attempt to diagnose them.

In todays world of abundant memory, we seldom worry about memory leakages. But I hate to tell you that we live in a real world and nothing comes for free.

Oh my fancy functional programming

Disclosure: I absolutely love functional programming. Functional programming is cool and with the new ES6 syntax it becomes even cooler.

kepta

function firstItem([first, second] = ['luke', 'skywalker']) {
  return first;
}

function findName({ name } = { name : 'darth' }) {
  return name;
}

kepta

const isRequired = () => { throw new Error('param is required'); };

function filterEvil(array, evil = isRequired()) {
  return array.filter(item => item !== evil);   
}

kepta

function whoIsEvilNow() {
  if (time > 2014) {
    return 'J. J. Abrams'
  }
  return 'darth vader';
}

function findEvil(array, evil = whoIsEvilNow()) {
  return array.find(item => item === evil);
}

kepta

function findEvil(array, evil = 'darth vader', respect = 'Bad ' + evil) {
  if (array.find(item => item === evil)) {
     return respect;
  }
}

findEvil(list); // Bad darth vader;

findEvil(list, 'luke'); // Bad luke;

kepta

const list = [ 'luke', 'leia', 'darth vader' ];
filterEvil(list, null); // [ 'luke', 'leia', 'darth vader' ]

kepta

function filterEvil(array, evil = 'darth vader') {
  return array.filter(item => item !== evil);   
}

kepta

function filterEvil(array, evil) {
  evil = evil || 'darth vader';
  return array.filter(item => item !== evil);
}

kepta

What's cooking at Mapbox this week

As a part of our data transparency efforts at Mapbox. We created osm-edit-report which helps anyone visualize our teams contribution to OSM.

Just to give a measure, the data team added 0.3 Million objects, 0.2 Million tags and 3 thousand changesets last week.

This is how the numbers look: