oPorks

/**
 * Variant of Avraham Plotnitzky's String.prototype method mixed with the "fast" version
 * see: https://sites.google.com/site/abapexamples/javascript/luhn-validation
 * @author ShirtlessKirk. Copyright (c) 2012.
 * Licensed under WTFPL (http://www.wtfpl.net/txt/copying)
 */

function luhnChk(luhn) {
    var len = luhn.length,
        mul = 0,

staltz

The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

CrossEye

function lens(get, set) {
  var f = function (a) { return get(a); };
  f.set = set;
  f.mod = function (f, a) { return set(a, f(get(a))); };
  return f;
}

var first = lens(
  function (a) { return a[0]; },
  function (a, b) { return [b].concat(a.slice(1)); }

adrianseeley

// based on http://msdn.microsoft.com/en-us/magazine/hh335067.aspx
// usage example at bottom

function pso (number_of_dimensions, function_to_optimize, number_of_particles, number_of_iterations, fitness_threshold, inertia_weight, cognitive_weight, social_weight) {
	var particles           = [];
	var swarm_best_position = [];
	var swarm_best_fitness  = null;
	for (var p = 0; p < number_of_particles; p++) {
		particles.push({
			particle_position:      [],

branneman

Better local require() paths for Node.js

Problem

When the directory structure of your Node.js application (not library!) has some depth, you end up with a lot of annoying relative paths in your require calls like:

const Article = require('../../../../app/models/article');

Those suck for maintenance and they're ugly.

Possible solutions

rauschma

/**
 * Create an array with `len` elements.
 * 
 * @param [initFunc] Optional: a function that returns
 * the elements with which to fill the array.
 * If the function is omitted, all elements are `undefined`.
 * `initFunc` receives a single parameter: the index of an element.
 */
function initArray(len, initFunc) {
    if (typeof initFunc !== 'function') {

hhauflaire

benmj

/*global angular: true, google: true, _ : true */

'use strict';

angular.module('geocoder', ['ngStorage']).factory('Geocoder', function ($localStorage, $q, $timeout) {
  var locations = $localStorage.locations ? JSON.parse($localStorage.locations) : {};

  var queue = [];

  // Amount of time (in milliseconds) to pause between each trip to the

buzzdecafe

(function(global) {

    global.Functor = function(conf) {
        Functor.types[conf.key] = {
            obj: conf.obj,
            fmap: conf.fmap
        };
    };
    
    Functor.types = {};

CrossEye

(function(global) {
    var types = function(obj) {
        throw new TypeError("fmap called on unregistered type: " + obj);
    };

    // inefficient as hell, but as long as there aren't too many types....
    global.Functor = function(type, defs) {
        var oldTypes = types;
        types = function(obj) {
            if (type.prototype.isPrototypeOf(obj)) {